[michaeldp]

Hi All,

Back with another problem, after getting my retrofit paddle shifter fixed...

I now have christmas lights on my dash and my wipers won't stop wiping (ended up pulling the fuse to stop so I can at least drive without embarrassment), below are the codes that I am getting and clearing error codes only makes it come back in an instant.

I have took it to the dealership and the only thing they did was clear codes & letting it power off completely and power it back on to drive it, and they drove it about 4 times and confirmed codes are not coming back, only to have them come back after 2 days. I have also replaced the battery from them. Completely at a lost...

Edit: I do have a Kenwood DMX9708S head unit & backup camera and sensor. With the christmas dash and Carplay going, I get no bass from the speakers and it seems like only the front speakers are working. Not sure if they are all related.

View post on imgur.com

View post on imgur.com

[gbalthrop]

First Suspect is Over-Voltage (System Voltage > 16V with engine running & Alternator Charging). When you have Intermittent "Light Show" or Wiper Self-activation, BEST way to confirm that Over-voltage caused those symptoms is via "Freeze Frame data". See this post for details:
https://www.e90post.com/forums/showp...7&postcount=14

Your 335i has different Voltage Regulator from N52K 328xi.
George

[michaeldp]

Originally Posted by gbalthrop

First Suspect is Over-Voltage (System Voltage > 16V with engine running & Alternator Charging). When you have Intermittent "Light Show" or Wiper Self-activation, BEST way to confirm that Over-voltage caused those symptoms is via "Freeze Frame data". See this post for details:
https://www.e90post.com/forums/showp...7&postcount=14

Your 335i has different Voltage Regulator from N52K 328xi.
George

I bought a multimeter and will be doing a test with the battery whenever I get home from work. Though the live data from MHD shows that my voltage is around 13.94v to 14.22v when I am driving with the codes. Not sure if that information is any help before I do the voltage test. Really appreciate your fast response.

[gbalthrop]

Originally Posted by michaeldp

I bought a multimeter and will be doing a test with the battery whenever I get home from work. Though the live data from MHD shows that my voltage is around 13.94v to 14.22v when I am driving with the codes...

When your "Light Show" or "Self-activating wipers" are intermittent, and ONLY happen occasionally when engine is running, that suggests your "Over-voltage" (which scrambles bus communications only when it occurs) is intermittent.

That means that "Freeze Frame data", which shows system voltage at moment code saved, MAY be BEST evidence. Otherwise, you have to "Catch it in the act", and view it as Live data at moment it occurs. There ARE other things that can "Scramble" bus communications. Over-voltage is most common.
George

[michaeldp]

Originally Posted by gbalthrop

When your "Light Show" or "Self-activating wipers" are intermittent, and ONLY happen occasionally when engine is running, that suggests your "Over-voltage" (which scrambles bus communications only when it occurs) is intermittent.

That means that "Freeze Frame data", which shows system voltage at moment code saved, MAY be BEST evidence. Otherwise, you have to "Catch it in the act", and view it as Live data at moment it occurs. There ARE other things that can "Scramble" bus communications. Over-voltage is most common.
George

It isn't really intermittent as the codes come right back after maybe 30 seconds starting the car. I am not too sure how the dealership was able to clear code because the codes won't clear on MHD, it comes right back.

I will try Freeze Frame Data to see if I can catch it.

[michaeldp]

Originally Posted by gbalthrop

When your "Light Show" or "Self-activating wipers" are intermittent, and ONLY happen occasionally when engine is running, that suggests your "Over-voltage" (which scrambles bus communications only when it occurs) is intermittent.

That means that "Freeze Frame data", which shows system voltage at moment code saved, MAY be BEST evidence. Otherwise, you have to "Catch it in the act", and view it as Live data at moment it occurs. There ARE other things that can "Scramble" bus communications. Over-voltage is most common.
George

Reporting the first part with the multimeter, nothing seem to be out of ordinary... apologies for the scuffed video, don't have camera stand. This is me trying to start the car.

View post on imgur.com

[gbalthrop]

Originally Posted by michaeldp

... the codes come right back after maybe 30 seconds starting the car... I will try Freeze Frame Data to see if I can catch it.

ALL 6 of the Fault Codes you posted indicate LACK of expected signal from DSC (4 to DME & 2 to EGS). The "BMW
Fault Code Lookup" Fault Info Sheet for each states in "Service Plan": "Carry out bus system analysis".

I use INPA & ISTA, BOTH of which can identify any Module (such as DSC) that is NOT communicating via PT-CAN Bus
(for DSC). I am NOT familiar with MHD. I attach ISTA ScreenPrints showing the PT-CAN Bus connection at the DSC
for your 2011 335xi.

I would suggest disconnecting the Connector X18303, at the dSC, and carefully inspecting the Pins/Sockets #15
(Red wire) & #30 (Blue/Red wire) for any moisture, corrosion, broken pin, enlarged/Loose Socket, etc. It would be
helpful to know if any OTHER Modules than DSC have communication issues. If NOT, then either the Connector at
DSC or the DSC itself is likely at fault. If you have ANY Scan Tool/ Software that can show DSC Live Data, see if there
is ANY communication with DSC.
George

[michaeldp]

Originally Posted by gbalthrop

ALL 6 of the Fault Codes you posted indicate LACK of expected signal from DSC (4 to DME & 2 to EGS). The "BMW
Fault Code Lookup" Fault Info Sheet for each states in "Service Plan": "Carry out bus system analysis".

I use INPA & ISTA, BOTH of which can identify any Module (such as DSC) that is NOT communicating via PT-CAN Bus
(for DSC). I am NOT familiar with MHD. I attach ISTA ScreenPrints showing the PT-CAN Bus connection at the DSC
for your 2011 335xi.

I would suggest disconnecting the Connector X18303, at the dSC, and carefully inspecting the Pins/Sockets #15
(Red wire) & #30 (Blue/Red wire) for any moisture, corrosion, broken pin, enlarged/Loose Socket, etc. It would be
helpful to know if any OTHER Modules than DSC have communication issues. If NOT, then either the Connector at
DSC or the DSC itself is likely at fault. If you have ANY Scan Tool/ Software that can show DSC Live Data, see if there
is ANY communication with DSC.
George

Do you have a guide on where to go in INPA? I tried going into INPA but it keeps giving me an error to compile script data... it used to work when I tried reading the FRM and recoding it.

Edit: OBD Auto Doctor won't pick up any connections either, I have a KCAN cable that can connect to the car + the MHD plug. Not sure why but only MHD is picking up connection.

Here are some photos I was able to get of the connector & pins, other than the flaky green white wire, I don't see pin 15 & 30 having a problem.

View post on imgur.com

[gbalthrop]

Originally Posted by michaeldp

... I tried going into INPA but it keeps giving me an error to compile script data... it used to work when I tried reading the FRM and recoding it... Not sure why but only MHD is picking up connection. Here are some photos I was able to get of the connector & pins, other than the flaky green white wire, I don't see pin 15 & 30 having a problem.

Once again, I am NOT familiar with MHD. I seem to recall posts suggesting you have to DISCONNECT something related to MHD, to enable INPA/ISTA connection.

ANYONE with MHD who can offer information?

What I DO KNOW: Windows Updates often resets COM Port settings. See "I. Procedure...", on 1st page of attached pdf, for HOW to RESET to "COM1" & Latency "1". AFTER checking those settings, see if you can connect & view the "Functional Jobs" screens: F2 Identification, to see what Modules are communicating. We are looking for "29 DSC". If you get an Error Message at any time when attempting to open "E90" or "Functional Jobs", please Save/Post ScreenPrint of that Error Message.

NOTE: The PT-CAN Bus wiring info I attached previously is for "NOT AWD". Sorry I didn't read the "fine print". NOW attached to NEXT Post are what I believe to be CORRECT ISTA diagrams for your 335xi (X-drive): (1) Power Supply (3 fuses), (2) X1746 Connector View (DSC/DXC used on AWD has different Connector), & (3) PT-CAN diagram confirming correct Pin#s.

CORRECT PT-CAN wires: (1) PT-CAN High: Blue/Red wire at X1746/37; (2) PT-CAN Low: Red wire at X1746/24.

Steps Suggested:
1) If INPA will show Functional Jobs > F2 Identification, see if "29 DSC" appears; If NO communication with DSC, most likely causes: a) NO power supply to DSC, or no Chassis Ground (Brown wires), b) faulty Bus wiring (here PT-CAN) to include connector issues, c) Module Internal Fault (LEAST Likely).

2) Inspect fuses F26, F82, F90; Test for 12V+ at X1746/25 (Red/Blue wire), X1746/1 (Red/Yellow wire), & X1746/7 (Red/Gray wire), the latter with Ignition ON (KL30G active).

3) Test for Continuity to Chassis Ground at EACH of the two Brown wires, X1746/13 & 38.

4) Inspect the Bus Pins/Sockets/Wires at X1746/37 & 24 (PT-CAN), & ALSO at X1746/26 & 14 (F-CAN).

5) You mentioned a "flaky green white wire", but did NOT explain. The White/Green wire shown on wiring diagram appears to be an OUTPUT signal from DSC related to RR Wheel Speed (speedometer signal?). An issue with OUTPUT Signal could possibly affect DSC function, so if steps ABOVE do NOT disclose an issue, please provide photo/ details re White/Green Wire.

Please let us know what you find.
George

[gbalthrop]

Attached are ISTA ScreenPrints related to Prior Post & 2011 335xi.
George

[michaeldp]

Originally Posted by gbalthrop

Once again, I am NOT familiar with MHD. I seem to recall posts suggesting you have to DISCONNECT something related to MHD, to enable INPA/ISTA connection.

ANYONE with MHD who can offer information?

What I DO KNOW: Windows Updates often resets COM Port settings. See "I. Procedure...", on 1st page of attached pdf, for HOW to RESET to "COM1" & Latency "1". AFTER checking those settings, see if you can connect & view the "Functional Jobs" screens: F2 Identification, to see what Modules are communicating. We are looking for "29 DSC". If you get an Error Message at any time when attempting to open "E90" or "Functional Jobs", please Save/Post ScreenPrint of that Error Message.

NOTE: The PT-CAN Bus wiring info I attached previously is for "NOT AWD". Sorry I didn't read the "fine print". NOW attached to NEXT Post are what I believe to be CORRECT ISTA diagrams for your 335xi (X-drive): (1) Power Supply (3 fuses), (2) X1746 Connector View (DSC/DXC used on AWD has different Connector), & (3) PT-CAN diagram confirming correct Pin#s.

CORRECT PT-CAN wires: (1) PT-CAN High: Blue/Red wire at X1746/37; (2) PT-CAN Low: Red wire at X1746/24.

Steps Suggested:
1) If INPA will show Functional Jobs > F2 Identification, see if "29 DSC" appears; If NO communication with DSC, most likely causes: a) NO power supply to DSC, or no Chassis Ground (Brown wires), b) faulty Bus wiring (here PT-CAN) to include connector issues, c) Module Internal Fault (LEAST Likely).

2) Inspect fuses F26, F82, F90; Test for 12V+ at X1746/25 (Red/Blue wire), X1746/1 (Red/Yellow wire), & X1746/7 (Red/Gray wire), the latter with Ignition ON (KL30G active).

3) Test for Continuity to Chassis Ground at EACH of the two Brown wires, X1746/13 & 38.

4) Inspect the Bus Pins/Sockets/Wires at X1746/37 & 24 (PT-CAN), & ALSO at X1746/26 & 14 (F-CAN).

5) You mentioned a "flaky green white wire", but did NOT explain. The White/Green wire shown on wiring diagram appears to be an OUTPUT signal from DSC related to RR Wheel Speed (speedometer signal?). An issue with OUTPUT Signal could possibly affect DSC function, so if steps ABOVE do NOT disclose an issue, please provide photo/ details re White/Green Wire.

Please let us know what you find.
George

I will check the connection settings to my computer & try to connect onto INPA. Will report back once I get a connection before I try to check for voltage & fuses. That will be my next step.

For the flaky green&white wire, I have circled it in the below picture, will that affect anything? When the error codes appear, my speedometer does go to 0 and won't move even when I am driving.

[BRG_N54]

Certainly sounds like all the classic voltage regulator symptoms. The voltage regulator is a consumable item, as it has brushes that wear over time and no longer work properly.

I usually suggest pulling up the voltage on the hidden KOMBI menu while driving. Voltage should be between 13.5V-14.5V, anything more or less points to a bad regulator. Only Bosch will do for a replacement part.

[michaeldp]

Originally Posted by BRG_N54

Certainly sounds like all the classic voltage regulator symptoms. The voltage regulator is a consumable item, as it has brushes that wear over time and no longer work properly.

I usually suggest pulling up the voltage on the hidden KOMBI menu while driving. Voltage should be between 13.5V-14.5V, anything more or less points to a bad regulator. Only Bosch will do for a replacement part.

The drive back home shows 13.7v - 13.9v, not sure if it's still voltage regulator issue. I have a N55 so the alternator is different. I have a Denso 170A alternator. It'd be pain in the ass to pull it out to replace the voltage regulator, but if it is the case I will do it. Though let me fiddle with INPA & ISTA and see if I can find anything out. Will report back once again.

[BRG_N54]

Originally Posted by michaeldp

The drive back home shows 13.7v - 13.9v, not sure if it's still voltage regulator issue. I have a N55 so the alternator is different.

Sorry, I missed that part, my experience is mostly N54. Voltage sounds normal, I like George's idea of "catching it in the act" to view live data.

[michaeldp]

Originally Posted by gbalthrop

Once again, I am NOT familiar with MHD. I seem to recall posts suggesting you have to DISCONNECT something related to MHD, to enable INPA/ISTA connection.

ANYONE with MHD who can offer information?

What I DO KNOW: Windows Updates often resets COM Port settings. See "I. Procedure...", on 1st page of attached pdf, for HOW to RESET to "COM1" & Latency "1". AFTER checking those settings, see if you can connect & view the "Functional Jobs" screens: F2 Identification, to see what Modules are communicating. We are looking for "29 DSC". If you get an Error Message at any time when attempting to open "E90" or "Functional Jobs", please Save/Post ScreenPrint of that Error Message.

NOTE: The PT-CAN Bus wiring info I attached previously is for "NOT AWD". Sorry I didn't read the "fine print". NOW attached to NEXT Post are what I believe to be CORRECT ISTA diagrams for your 335xi (X-drive): (1) Power Supply (3 fuses), (2) X1746 Connector View (DSC/DXC used on AWD has different Connector), & (3) PT-CAN diagram confirming correct Pin#s.

CORRECT PT-CAN wires: (1) PT-CAN High: Blue/Red wire at X1746/37; (2) PT-CAN Low: Red wire at X1746/24.

Steps Suggested:
1) If INPA will show Functional Jobs > F2 Identification, see if "29 DSC" appears; If NO communication with DSC, most likely causes: a) NO power supply to DSC, or no Chassis Ground (Brown wires), b) faulty Bus wiring (here PT-CAN) to include connector issues, c) Module Internal Fault (LEAST Likely).

2) Inspect fuses F26, F82, F90; Test for 12V+ at X1746/25 (Red/Blue wire), X1746/1 (Red/Yellow wire), & X1746/7 (Red/Gray wire), the latter with Ignition ON (KL30G active).

3) Test for Continuity to Chassis Ground at EACH of the two Brown wires, X1746/13 & 38.

4) Inspect the Bus Pins/Sockets/Wires at X1746/37 & 24 (PT-CAN), & ALSO at X1746/26 & 14 (F-CAN).

5) You mentioned a "flaky green white wire", but did NOT explain. The White/Green wire shown on wiring diagram appears to be an OUTPUT signal from DSC related to RR Wheel Speed (speedometer signal?). An issue with OUTPUT Signal could possibly affect DSC function, so if steps ABOVE do NOT disclose an issue, please provide photo/ details re White/Green Wire.

Please let us know what you find.
George

George, I think I need some more help... I am a electrical dummy, 0 experience. Where do I go from here?

I am computer savvy, and was able to get ISTA to work. Seems like it's just showing the code like MHD anyways. Where do I go from here?

[gbalthrop]

Originally Posted by michaeldp

... I am computer savvy, and was able to get ISTA to work. Seems like it's just showing the code like MHD anyways. Where do I go from here?

Since you NOW have ISTA running, we want to see "Control Unit Tree", & see if DSC is "RED" (NOT communicating). See attached PDF: "Fault Memory & Test Plan", page 3, & SAVE/ Post here the "Control Unit Tree". See "VIII. Saving/ Posting ScreenPrints" at bottom of page 9 of pdf.

See also the steps suggested in Post #11, where I attached CORRECT ISTA ScreenPrints. I'll check your new Fault Memory Screens and let you know if I have any additional Ideas.

George

[gbalthrop]

I see your initial Post in this Thread states: "Back with another problem, after getting my retrofit paddle shifter fixed..."

Your latest Fault Codes suggest you have NO communication with DSC Module, or with MOST Bus components. I would expect the DSC Module to be RED on the Control Unit Tree Screen, along with some/ALL the Modules on MOST Bus (Head Unit, Telephone, Sat).

It is possible that you have a Bus communication issue that was caused by improper reinstallation of SZL (Steering Column Switch Center) connectors/ wiring by WHOMEVER. I do NOT immediately see any relationship between the DSC bus issues & MOST however.

I have NOT personally had to diagnose a Bus issue, so others MAY have better ideas. You might simply rely on ISTA Test Plan, which you enter by selecting one of the Codes related to NO Message from/ Communication with, DSC, as shown in PDF previously attached. ALSO, do Steps outlined in Post #11.
George

[michaeldp]

Originally Posted by gbalthrop

I see your initial Post in this Thread states: "Back with another problem, after getting my retrofit paddle shifter fixed..."

Your latest Fault Codes suggest you have NO communication with DSC Module, or with MOST Bus components. I would expect the DSC Module to be RED on the Control Unit Tree Screen, along with some/ALL the Modules on MOST Bus (Head Unit, Telephone, Sat).

It is possible that you have a Bus communication issue that was caused by improper reinstallation of SZL (Steering Column Switch Center) connectors/ wiring by WHOMEVER. I do NOT immediately see any relationship between the DSC bus issues & MOST however.

I have NOT personally had to diagnose a Bus issue, so others MAY have better ideas. You might simply rely on ISTA Test Plan, which you enter by selecting one of the Codes related to NO Message from/ Communication with, DSC, as shown in PDF previously attached. ALSO, do Steps outlined in Post #11.
George

You are correct, the DSC on the Control Unit Tree Screen is red along with other modules being yellow. Before I made the post, I did check fuse F26, F82, and F90 and they are all fine with no disconnections in the fuse. How do I go about testing the voltages? Can you please show me where positive and negative of the wires are to test for voltage?

I did find a post from 2022 that had the same exact issues, and all this guy did was a adaptation reset. Before I rip out the steering wheel and check out how bad I damaged it, how do I go about resetting the adaptations?

Here's the post: https://www.e90post.com/forums/showthread.php?t=1900167

This is the retrofit that I did for the paddle shifters, not sure how I can mess up the communication with other modules. Additionally, I did the retrofit about 8 months ago, and everything was working fine until 2 weeks ago.

[The Nightman]

I had a similar problem after retrofitting paddle shifters and it turned out I didn't plug in the steering wheel harness completely. Worth a check

Step 16 in BMS's instructions: https://www.jb4tuned.com/instruction...tall-Guide.pdf

"Problem: DTC error codes, erratic windshield wipers, and other malfunctions.
Cause: Harness cover with gray swivel bar loose, improperly connected, not locked in or harness inside is backwards. Factory harness is upside down on in steering column. Incorrect pins were removed."

[michaeldp]

Originally Posted by The Nightman

"Problem: DTC error codes, erratic windshield wipers, and other malfunctions.
Cause: Harness cover with gray swivel bar loose, improperly connected, not locked in or harness inside is backwards. Factory harness is upside down on in steering column. Incorrect pins were removed."

Just spent an hour taking all the steering stuff out and double checking the wires & harness... everything came out and went back in perfectly fine, without the need of force. Though I only tried it with the accessory mode on and it is still throwing the same codes. Didn't start the car because it was getting too late. Will try to start tomorrow to see if anything clears. Will report back.

[gbalthrop]

Originally Posted by michaeldp

... DSC on the Control Unit Tree Screen is red along with other modules being yellow. Before I made the post, I did check fuse F26, F82, and F90 and they are all fine with no disconnections in the fuse. How do I go about testing the voltages? Can you please show me where positive and negative of the wires are to test for voltage?...

If everything was "Fine" for 6 months after Steering Wheel Removal, I would focus on the X1746 Connector at the DSC/DXC Module. I'll put ALL the tests here, that were previously-described in Post #9. Refer to Post #10 for the ISTA wiring diagrams, and please Ask Questions about those wiring diagrams, as it takes different SKILLS to "Read wiring diagrams" than to do mechanical R&R's.

General Multimeter Readings:
1. Voltage Test: To measure Voltage at a Connector Socket:

a) Set meter to "DC Volts" (Direct Current); Select 20V (meaning LESS than 20 Volts Direct Current);

b) Place RED Meter Probe on METAL Socket of Connector; contact Chassis Ground (good UN-painted Chassis Metal) with Black Meter Probe;

c) Science Lab/ Test/ to REALLY LEARN: If you have NOT used Multimeter recently, Test by measuring Voltage at Jumpstart Terminals under Hood: Red Meter Probe on B+ metal under Red Plastic Cap; Black Meter Probe on Hex-Pin on Right Wing/Fender, or any other good Chassis Metal. Meter should read "12.x V". If you reverse polarity (Black probe on B+) you will simply get a NEGATIVE (-) reading, without damaging anything. You can practice on 1.5 V "Dry Cell" battery. Just change DC Volts Range Setting to "2" meaning 2V DC or Less. To test small 9V battery, return to 20V Range Setting.

When measuring Voltage, you are measuring "Electrical Potential", which is analogous to comparing pressure vs. vacuum -- High pressure on one side, Low pressure on other; but there is NO "Current Flow" through meter.

2. Specific Tests, Please Report Values Measured:

ISTA shows NO communication with DSC, most likely causes:
a) NO power supply to DSC, or no Chassis Ground (Brown wires), b) faulty Bus wiring (here PT-CAN) to include connector issues, c) Module Internal Fault (LEAST Likely).

Disconnect X1746 Connector at the DSC; Identify Socket #25, LARGE Red/Blue wire; Socket #1, LARGER Red/Yellow wire; & Socket #7, Small Red/Gray wire. You want to measure DC Voltage at EACH of those Sockets with Connector DIS-connected from DSC. IF ANY socket number or wire color does NOT conform to above, let us know HOW your socket differs.

1) Test for 12V+ at X1746/25 (Red/Blue wire), X1746/1 (Red/Yellow wire), & X1746/7 (Red/Gray wire), the latter with Ignition ON (KL30G active). Red Meter Probe contacting Metal Socket of Connector, & Black Meter Probe contacting Chassis Ground. As example, if NO voltage at small Red/Gray wire, X1746/7 Socket, with Ignition ON, there is an issue with F26 Fuse/ wiring.

2) Identify the Bus Sockets/ Wires from the wiring diagram. They are the SMALL Red/Blue, Red, White/Yellow & White/Blue wires at the Sockets named BELOW.

Inspect the Bus Pins/Sockets/Wires at X1746/37 & 24 (PT-CAN), & ALSO at X1746/26 & 14 (F-CAN). Look for any Broken Pin, Enlarged Socket, damage to pin/ socket/ wire insulation, corrosion/ rust, etc. If in doubt take photo & attach here. Use "Electronic Contact Cleaner" such as CRC Brand, to GENTLY clean connector sockets & Module Pins.

I don't see anything but perhaps mildew, white powder (salt?) or other external coating on your White/Green "flaky" wire. Unless the insulation is cut or damaged, we're MORE Concerned with metal pins/ sockets on OTHER face of Connector.

There are OTHER tests which may be "Indicated", but I would suggest taking time to do the Tests above, getting comfortable/ CONFIDENT of your Multimeter Testing Skills. As with ANY new skill, it takes THOUGHT & Practice. Develop your OWN CONCEPTS of HOW things work.

OLD "Analog" model for understanding Electricity, Volts, Amps, Ohms:
1) Voltage or Electrical Potential is Analogous (similar) to Water pressure. Even with Spigot/Valve closed, and NO water flowing, there is Pressure in the Pipe.

2) Ohms or Resistance is Analogous to Pipe Size or Valve/Spigot opening. Infinite resistance (open electrical "circuit") is similar to CLOSED Valve, preventing any flow. ZERO Resistance/Ohms is a "Short-Circuit-to-Ground" or
open water main, with virtually NO resistance to Flow.

3) Amperes or Current Flow Rate is Analogous to Water Flow Rate (GPM/ Gallons Per Minute). Since "Current" has to flow THROUGH a Multimeter to measure "Amps", I would suggest ONLY doing that AFTER you have mastered OTHER Tests and have specific guidance. Clamp (induction) meter is best for larger current flow measurements, and you do NOT have to open the circuit.
George

[michaeldp]

Originally Posted by gbalthrop

1) Test for 12V+ at X1746/25 (Red/Blue wire), X1746/1 (Red/Yellow wire), & X1746/7 (Red/Gray wire), the latter with Ignition ON (KL30G active). Red Meter Probe contacting Metal Socket of Connector, & Black Meter Probe contacting Chassis Ground. As example, if NO voltage at small Red/Gray wire, X1746/7 Socket, with Ignition ON, there is an issue with F26 Fuse/ wiring.

2) Identify the Bus Sockets/ Wires from the wiring diagram. They are the SMALL Red/Blue, Red, White/Yellow & White/Blue wires at the Sockets named BELOW.

Inspect the Bus Pins/Sockets/Wires at X1746/37 & 24 (PT-CAN), & ALSO at X1746/26 & 14 (F-CAN). Look for any Broken Pin, Enlarged Socket, damage to pin/ socket/ wire insulation, corrosion/ rust, etc. If in doubt take photo & attach here. Use "Electronic Contact Cleaner" such as CRC Brand, to GENTLY clean connector sockets & Module Pins.

I don't see anything but perhaps mildew, white powder (salt?) or other external coating on your White/Green "flaky" wire. Unless the insulation is cut or damaged, we're MORE Concerned with metal pins/ sockets on OTHER face of Connector.

There are OTHER tests which may be "Indicated", but I would suggest taking time to do the Tests above, getting comfortable/ CONFIDENT of your Multimeter Testing Skills. As with ANY new skill, it takes THOUGHT & Practice. Develop your OWN CONCEPTS of HOW things work.

OLD "Analog" model for understanding Electricity, Volts, Amps, Ohms:
1) Voltage or Electrical Potential is Analogous (similar) to Water pressure. Even with Spigot/Valve closed, and NO water flowing, there is Pressure in the Pipe.

2) Ohms or Resistance is Analogous to Pipe Size or Valve/Spigot opening. Infinite resistance (open electrical "circuit") is similar to CLOSED Valve, preventing any flow. ZERO Resistance/Ohms is a "Short-Circuit-to-Ground" or
open water main, with virtually NO resistance to Flow.

3) Amperes or Current Flow Rate is Analogous to Water Flow Rate (GPM/ Gallons Per Minute). Since "Current" has to flow THROUGH a Multimeter to measure "Amps", I would suggest ONLY doing that AFTER you have mastered OTHER Tests and have specific guidance. Clamp (induction) meter is best for larger current flow measurements, and you do NOT have to open the circuit.
George

So I got my friend to help remotely (discord call xD), and we were able to get some voltages out of the pins you were looking for. The extra one that we tested was the one with corrision (white/green wire), and it has no voltage so we weren't sure if it's a ground cable. Also not sure if ignition ON means turning on the car and testing, will do that once confirmed. Thanks again for all the information.