[platano_4life]

Originally Posted by gbalthrop

Another Reason NOT to rely on videos, as MOST folks who make a video have NOT learned that not ALL BMW's are alike, don't know when the changes occurred, or don't want to take the time to explain it. The JB (Junction Box) Fuse Panel LAYOUT changed 3/1/2007 in the middle of the model run, but fuse numbering, by Function, remained the same, resulting in "scrambled fuse Numbering". Numbering was changed effective 9/1/2007 for 2008 models so that fuse numbers generally increased in order, Left-to-right, top-to-bottom, and remained the same for remainder of E9x run. ALSO, the contents of the E-box were simplified effective 3/1/2007. The ONLY relay you have in the E-box is the Fan Cutout Relay (REMEMBER that little gem from Post #8? ;-)

ONLY fuse you have in the E-box AFAIK is F07 which powers the Coolant Pump. Did you check that Fuse, and also F37 on the JB Fuse Panel. BOTH need to be intact for the Coolant Pump to operate.



If the good pump has good fuses, wiring, and CONNECTORS, Yes.
I understand the "cramped quarters" where the 335xi Pump and T-Stat are located, although I have NOT personally done an R&R. HOWEVER, if the connector is difficult to separate, that suggests the pins/ sockets may be corroded, or the pump may be leaking coolant on the connector. Sooner or later, you are going to HAVE to figure out HOW to disconnect X6035 Connector at the Pump.

ONLY reliable way to test the Voltage Supplies (2), Ground, and BSD Speed Signal voltage is AT the Connector. I'm LAZY. IF there were an easier way, I'd try to find it. I can't think of any.

Make sure you are looking at the LARGER Pump 4-pin connector, and NOT the smaller 2-pin T-Stat Connector. If you still have an issue trying to disconnect X6035, post back and ask for help from someone who has DONE that. Some folks have described jacking the car, removing RF wheel and RF Fender Liner to get better access to Pump & T-stat, particularly on x-Drive. That small Orange wire at X6035/1 MAY be the issue.
George

Thanks again. I can probably figure out how to get the Pump out with time I just don't always have alot of time when jacking the car up. I ordered the water pump, thermostat, and coolant from FCP Euro, ill post back here after I get everything installed and let you know how everything went. Also. What did you mean when you said the small Orange Wire may be the issue?

[gbalthrop]

Originally Posted by platano_4life

... What did you mean when you said the small Orange Wire may be the issue?

Orange wire from fuse F37 to X6035/1. Either the Fuse, the wire, or more likely that Socket at the Connector.
To avoid "throwing parts", it's a good idea to test for Voltage (both fuses), Continuity to Ground, and Speed Signal
Voltage at the Connector.
George

[platano_4life]

Originally Posted by gbalthrop

Another Reason NOT to rely on videos, as MOST folks who make a video have NOT learned that not ALL BMW's are alike, don't know when the changes occurred, or don't want to take the time to explain it. The JB (Junction Box) Fuse Panel LAYOUT changed 3/1/2007 in the middle of the model run, but fuse numbering, by Function, remained the same, resulting in "scrambled fuse Numbering". Numbering was changed effective 9/1/2007 for 2008 models so that fuse numbers generally increased in order, Left-to-right, top-to-bottom, and remained the same for remainder of E9x run. ALSO, the contents of the E-box were simplified effective 3/1/2007. The ONLY relay you have in the E-box is the Fan Cutout Relay (REMEMBER that little gem from Post #8? ;-)

ONLY fuse you have in the E-box AFAIK is F07 which powers the Coolant Pump. Did you check that Fuse, and also F37 on the JB Fuse Panel. BOTH need to be intact for the Coolant Pump to operate.



If the good pump has good fuses, wiring, and CONNECTORS, Yes.
I understand the "cramped quarters" where the 335xi Pump and T-Stat are located, although I have NOT personally done an R&R. HOWEVER, if the connector is difficult to separate, that suggests the pins/ sockets may be corroded, or the pump may be leaking coolant on the connector. Sooner or later, you are going to HAVE to figure out HOW to disconnect X6035 Connector at the Pump.

ONLY reliable way to test the Voltage Supplies (2), Ground, and BSD Speed Signal voltage is AT the Connector. I'm LAZY. IF there were an easier way, I'd try to find it. I can't think of any.

Make sure you are looking at the LARGER Pump 4-pin connector, and NOT the smaller 2-pin T-Stat Connector. If you still have an issue trying to disconnect X6035, post back and ask for help from someone who has DONE that. Some folks have described jacking the car, removing RF wheel and RF Fender Liner to get better access to Pump & T-stat, particularly on x-Drive. That small Orange wire at X6035/1 MAY be the issue.
George

I took the pump out this morning and noticed that the thermostat was not replaced when the water pump was, and also the new water pump was a Chinese brand . power was good at the actual connector. I went to a buddy of mine that has access to worldpac and ordered a new oem waterpump and thermostat. Spent $470 after coolant and taxes. just finished installing it and the car runs like a dream.
I find it weird that the car didn't throw a code for the water pump. Ah well lol. Thank you gba for all the help you are a God

[bkwld]

I just can’t believe we have member like George here. He is so helpful to take the time on this forum. This is what makes it great! I appreciate this.

[mkmars]

Hey Guys,
Great info here. I have a problem with my fan (2009 328i). It does not work at all. I have followed gbalthrop's instructions. All fuses are good. Relays checked okay. With ignition on, I have 12V at the Red/Blue, and around 4.40 at the signal wire {Black/Blue). The signal voltage does not change with AC powered on with and without engine running. This has puzzled me since no voltage change happens with signal wire.
I have also changed all Temp sensors but I get three codes which are labeled as permanent and can not erase them with my scanner.
They are P0118, P3198 and P00B3.

Need Help.

[kaaayelll]

Originally Posted by gbalthrop

The short answer to your question is: "You DON'T".

The E-Fan has a built-in Electronic Control. If you had INPA/ISTA, you could "Activate" the fan by sending a speed
signal via the Black/Blue wire to Pin #4 of Connector X1797. HOWEVER, you CANNOT get the Fan to run by applying
12V+ & Ground to the two large wires, Red/Blue at Pin#2 & Brown at Pin #1. If the fan electronics are NOT already
damaged, you would likely damage them by applying 12V+ to Pin #4 (the small wire).

See the attached ISTA ScreenPrints showing the Fan Wiring Diagram, Power supply, Lines ID, & X1797 Connector View.
If you do NOT have INPA/ISTA or something that can "Activate" the E-Fan, about all you can do is test as follows:
1) With engine running, turn on A/C Compressor. At stationary idle, fan should operate at slower speed
within 30 seconds of turning on A/C.
2) If NO E-Fan operation, turn engine OFF, and disconnect Connector X1797 from the Fan Unit.
3) With Ignition ON (engine still OFF), using Multimeter, measure Voltage in Reference to Chassis Ground at Pin#2, Red/Blue wire.
4) Check for continuity to Ground at Pin #1, Brown wire.
5) Test for Voltage at Pin #4, Black/Blue small wire, in reference to chassis ground:

a) with A/C Compressor (Snowflake) OFF but engine running;
b) with A/C Compressor ON and engine running.

Please let us know your results.
George

This thread has been super helpful as I try to diagnose my cooking fan issue. Thanks so much to all!

I’ve checked fuses, confirmed continuity of the Brown ground wire, and confirmed 12 volts to the Red/Blue wire. The voltage on the Black/Blue control wire seems quite low at 0.28 or so vs about 4.0 from what I've read of others' experience. Also, the error code I'm receiving is 31E8, "Electric fan, actuator: Short circuit to ground." The fan does turn on when activated with a scan tool.

Any advice regarding likely location of the short? Thanks in advance.

Vehicle is a 2011 335i X-Drive sedan, btw.

[gbalthrop]

Originally Posted by kaaayelll

...confirmed continuity of the Brown ground wire, and confirmed 12 volts to the Red/Blue wire. The voltage on the Black/Blue control wire seems quite low at 0.28 or so vs about 4.0 from what I've read of others' experience. Also, the error code I'm receiving is 31E8, "Electric fan, actuator: Short circuit to ground." The fan does turn on when activated with a scan tool...Vehicle is a 2011 335i X-Drive sedan, btw.

Here is the BMW Fault Code Lookup Definition of that code, with Link to Fault Info Sheet which gives clues on diagnosis:
31E8 | Electric fan, activation: Short circuit to ground | MEVD176K | Engine electronics
https://bmwfault.codes/XMLDiagView?d...cAOQAyADAANAA=

It appears the Black/Blue "Activation" wire is damaged and "Shorted-to-chassis Ground" somewhere between the Fan Connector and the DME Connector X60001/20 (Socket #20 of Connector X60001).

I would suggest disconnecting BOTH the Fan Connector, X1797, and the DME Connector, X60001, and testing for Resistance/ Continuity to Chassis Ground at either/both ends of the Black/Blue wire, X1797/4, and X60001/20. Both readings SHOULD be same, and if resistance close to 0, you have short to ground in that wire. ISTA Wiring Diagram ScreenPrint, with Connector Location & Connector View of X60001 Connector are attached to NEXT Post.

I have NO IDEA how to locate the short after testing to confirm its existence, and have never worked on N55. Hopefully there is something obvious to careful inspection near connector at either end, and/or you have some clues from recent work done in that area. The 0.28V at X1797/4 suggests a pinched wire, or damaged insulation at some point in the harness.

Please let us know what you find,
George

[gbalthrop]

Attached are ISTA ScreenPrints of Radiator Fan wiring for 2011 335xi E90 & Connector Location/View of X60001
per Prior Post.
George

[kaaayelll]

Thanks so much. I will be doing further diagnostic soon and will be certain to come back. Thankfully, the car is not getting hot when driving, but I don't want the issue to go on much longer.

[kaaayelll]

Originally Posted by gbalthrop

Attached are ISTA ScreenPrints of Radiator Fan wiring for 2011 335xi E90 & Connector Location/View of X60001
per Prior Post.
George

Before I could get to further diagnostics, the weather got warmer and the fan showed itself to be working. It’s not clear to me why it didn’t work by switching on the AC in the colder weather.

[JonOhh]

Regarding the water pump and fan control system - good diagnostic procedures aside (George's advice is more in line with how tests should be carried out) - if given 12v, and communication over BSD is interrupted while the module is awake, the fan should resort to full or near full speed operation. Depending on the production date of the waterpump (and if it's a pierburg pump) it should also resort to around 90% speed in the event communication stops.

But again, I don't think using this fail safe is a good way to go about diagnosing, personally. Definitely follow the ISTA procedures first, and play around with INPA.

[Derek Keenan]

Originally Posted by gbalthrop

The short answer to your question is: "You DON'T".

The E-Fan has a built-in Electronic Control. If you had INPA/ISTA, you could "Activate" the fan by sending a speed
signal via the Black/Blue wire to Pin #4 of Connector X1797. HOWEVER, you CANNOT get the Fan to run by applying
12V+ & Ground to the two large wires, Red/Blue at Pin#2 & Brown at Pin #1. If the fan electronics are NOT already
damaged, you would likely damage them by applying 12V+ to Pin #4 (the small wire).

See the attached ISTA ScreenPrints showing the Fan Wiring Diagram, Power supply, Lines ID, & X1797 Connector View.
If you do NOT have INPA/ISTA or something that can "Activate" the E-Fan, about all you can do is test as follows:
1) With engine running, turn on A/C Compressor. At stationary idle, fan should operate at slower speed
within 30 seconds of turning on A/C.
2) If NO E-Fan operation, turn engine OFF, and disconnect Connector X1797 from the Fan Unit.
3) With Ignition ON (engine still OFF), using Multimeter, measure Voltage in Reference to Chassis Ground at Pin#2, Red/Blue wire.
4) Check for continuity to Ground at Pin #1, Brown wire.
5) Test for Voltage at Pin #4, Black/Blue small wire, in reference to chassis ground:

a) with A/C Compressor (Snowflake) OFF but engine running;
b) with A/C Compressor ON and engine running.

Please let us know your results.
George

Hey I know this thread is old but on my 335 my radiator fan won’t turn on when I turn ac on but it turns on when the car warms up, I followed your electrical diag steps and got 12 volts on pin 2 with car compressor on/ accessory mode, continuity on pin 2 is good, no continuity on pin 4. Any help?