[nuron]

Where is this relay located? I've read multiple threads of it being in the passenger wheel well, in the DME box under the hood, etc.

Trying to chase down the reason why my radiator fan hasn't been turning on--my checklist of items are:

-Check fuse behind glove box: looks good
-Try engaging fan in INPA--will have to see which menu this is located. The fan doesn't turn on when the A/C is activated.
-Radiator fan relay
-Check fan motor itself (somehow). If the fan itself is bad, FCP Euro has Mishimoto universal fans that I may try--anyone ever try this option? The OEM fan is super expensive.

Thanks in advance.

[gbalthrop]

WHAT are Last-7 Characters of your VIN? Many electrical changes 3/1/2007 in middle of 2007 model run.

To Activate the Fan using INPA:
INPA > DME (Engine | MSV80 for N52K) > F6 Activations > F1 Activations Group 1 > F2 E-Fan (Choose between 15%, 50% or 90%).

The reason a proper replacement is so expensive is that the Control Electronics for the Fan unit (to run at different speeds) are incorporated in the Fan Unit. So spend some time doing proper testing (AFTER you identify your VIN so I can provide correct wiring diagrams from ISTA), rather than throwing parts.
George

[nuron]

Originally Posted by gbalthrop

WHAT are Last-7 Characters of your VIN? Many electrical changes 3/1/2007 in middle of 2007 model run.

To Activate the Fan using INPA:
INPA > DME (Engine | MSV80 for N52K) > F6 Activations > F1 Activations Group 1 > F2 E-Fan (Choose between 15%, 50% or 90%).

The reason a proper replacement is so expensive is that the Control Electronics for the Fan unit (to run at different speeds) are incorporated in the Fan Unit. So spend some time doing proper testing (AFTER you identify your VIN so I can provide correct wiring diagrams from ISTA), rather than throwing parts.
George

Thanks for the help gbalthrop. Will try that in INPA and update this thread. The last 7 of my VIN is: FV65274. Looks like production date was 02/2007.

[nuron]

I was able to activate the fan via INPA through all the power levels (I think it was 15%, 50%, and 90%).

Not sure what else it could be. I read somewhere that someone had their A/C pressure too low, and when it was recharged to spec, the fan started working again. Might have to rent the AC gauges at Autozone and give it a go.

Would still be good to know the relay location just in case.

[gbalthrop]

Originally Posted by nuron

I was able to activate the fan via INPA through all the power levels (I think it was 15%, 50%, and 90%).
... I read somewhere that someone had their A/C pressure too low, and when it was recharged to spec, the fan started working again. Might have to rent the AC gauges at Autozone and give it a go.
Would still be good to know the relay location just in case.

NO Relay on 2/2007 build E9x models:
The relay is located in Models built a Month AFTER yours. I'll attach an ISTA ScreenPrint of the Engine Cooling System, showing the E-Fan circuit that has NO "Cut-out Relay". The cutout relay was used in models built AFTER 3/1/2007, to allow the Fan to run for a minute or two AFTER engine shutdown. My 3/14/2007 build 328xi has that relay, but I have NEVER heard the E-fan run after engine shutdown, so don't feel like you're missing something. It MIGHT be valuable on the N54.

Fan Electronics and Speed Signal Wiring OK:
The "T_ELUE" Line (Black/Blue wire) is the speed signal that tells the Fan when to run, and HOW Fast. Note the ISTA Lines ID Description says: "Signal, electric fan relay", BUT there is NO relay. The "Signal" is likely a PWM signal (Pulse Width Modulated), and as the Duty Cycle or Frequency increases, the Fan runs at a speed based upon that "Signal Frequency".

If the Actual Speed of the E-Fan approximates the 15%, 50% or 90% Activation Speed when Activated using INPA > F6 > F1 > F2, then the fan is working properly. BTW, you can use that "F6 > F1 > F2 Activation" Screen to simply VIEW/ Observe operation of Fan and ECTS Temp Signal as received by the DME. You just open the screen but do NOT select F1 - F3 to over-ride DME Control of Fan Speed (15%, 50% or 90%). Other "Activation" screens are similar, such as Coolant Pump, T-Stat, etc.

NOTE: that on 328i/xi with N52 engine, there is NO ROTS (Radiator Outlet Temp Sensor) on the Bottom Radiator Hose. The DME Calculates the ROTS signal as ALWAYS 7.5C LESS than the ECTS (Engine Coolant Temp Sensor) Signal. So make sure your ECTS Actual Temp is what is shown in the INPA Screen. If you have an Infrared Thermometer, just point it at the ECTS on the front of the OFH, and see if the temp reading/ signal correlate.

You can use that SAME INPA screen to see if/when the Fan begins to run, at what ECTS Temp, and at WHAT speed, with A/C turned OFF. The following is an excerpt from Bentley Manual 170-3, pdf page 356, , describing INPUTS used by DME to control E-Fan:
"Electric fan activation is based on the following inputs to the ECM:
• Radiator outlet temperature
• Calculated catalytic converter temperature
• Vehicle speed
• Battery voltage
• Calculated refrigerant pressure"

Refrigerant Pressure; A/C "Charge":
You don't need Manifold Gauges since you have INPA. Just connect to the IHKA Module (or JBE module) and view/ save/ post the following screen:
INPA > IHKA (Body | Air Conditioning / Control Panel) > F5 > F1 Analog Inputs/Ports
Refrigerant Pressure Sensor Signal is at bottom-left of screen, and Evaporator Temp is next to bottom in right column. BimmerGeeks "translators" cleverly translated Refrigerant Pressure as "Print Cooling Agent" -- which actually is ONE translation of Druck (Print/ Press / Pressure) Kältemittel (Refrigerant) kälte (cold) mittel (Medium/ Agent).

Moral to the story: Stuff happens; The volunteers who translated the BimmerGeeks version of INPA did a good job overall. If you see something that doesn't make sense, let us know & Google Translate offers multiple synonyms for German words, which have MULTIPLE meanings. "Context" is everything, and it pays to know the correct English Technical Terminology.

I would suggest doing the following after car has sat with engine off for an hour or two (or more). The "High Side" (where the Refrigerant Pressure Sensor is located) and the "Low Side" are at "equilibrium", meaning a manifold gauge connected to BOTH ports (High & Low) would read SAME value, as "High side" pressure and "Low side" pressure have equalized in an hour or more.

If that pressure is TOO LOW, the JBE will NOT allow the Compressor to run. That is similar to a Low Pressure Switch on older A/C compressors, to prevent damage to compressor from being run with NO lubrication from refrigeration oil circulating with Refrigerant. Equilibrium pressure SHOULD be in range of 6 bar or slightly more. If refrigerant leaks, and equilibrium pressure is LESS than ~ 3 bar, the compressor will likely NOT run.

HOW to use INPA to assess Refrigerant Pressure/ Charge:
1) Connect the K+DCAN Cable, open INPA, turn on ignition but do NOT start engine; select:
2) INPA > IHKA (Body | Air Conditioning / Control Panel) > F5 > F1 Analog Inputs/Ports;
3) Read and record the Refrigerant Pressure (in bar, where one bar = 14.5 PSI; remember Manifold Gauges read PSIG (Gauge) and bar is "absolute".
4) Now with A/C Control Panel ON, Compressor "Snowflake" LED lighted, START engine and monitor Refrigerant Pressure. If NO change, AND the Evaporator Temp does NOT decrease, the compressor is NOT pumping. If Refrigerant Pressure increases over the "Equilibrium" pressure read earlier, NOTE the reading after about 20 seconds (save screenprint).

As long as you have SOME pressure > 1 bar, you can just add refrigerant without evacuating. Let us know what you find in those tests, and we can suggest how to DIY refrigeration, in a professional manner. You might want to consider spending ~ $35 (Amazon) for Manifold Gauges and Can Tap. R-134a 12-oz can currently $9 at Walmart.
George

[gbalthrop]

Attached are ScreenPrints, ISTA & INPA, as referenced in prior post.
George

[nuron]

You're a treasure trove of information! No way would I have been able to find this information on my own haha. I'm out of town for the next couple days but will report back with my findings.

If I end up needing to recharge the system, I've done it before with the rental manifold gauges kit from Autozone and a couple cans of pure refrigerant.

[shushikiary]

Do you guys happen to know the peak voltage and frequency of the PWM signal the ECU sends to the fan?

I'm looking to using the same PWM output to drive another fan control unit like the dorman 902-310. They appear to be 12v PWM in and output the same frequency as they get in, but there as some mazda/ford/chevy control units I could use as well depending on what the BMW control scheme is.

It would also be nice to know if the max PWM frequency is below 100%.

[gbalthrop]

Originally Posted by shushikiary

Do you guys happen to know the peak voltage and frequency of the PWM signal the ECU sends to the fan?... It would also be nice to know if the max PWM frequency is below 100%.

If you're looking to install a replacement E-Fan unit in your 2008 335xi, I would suggest the $30 Clamp Meter linked below which can measure Duty Cycle or Frequency of PWM signal at X1797/4 (Black/Blue wire). Duty Cycle % should increase noticeably when A/C Compressor Valve is switched on.

That clamp meter can also measure DC Current (Amps) simply clamping a wire/cable, instead of opening circuit, particularly handy in Diagnosing Draw > 100 mAmp:
https://www.amazon.com/Electrical-Au...xpY2s9dHJ1ZQ==

There SHOULD be a DC Volts reading which increases/ fluctuates in relationship to the Duty Cycle % value, but I have never tested any PWM (E-Fan, Coolant Pump, etc.) signal for exact values. I know there is a Coolant Pump Test SIB which states the speed signal should be 7.5 to 8.5 V DC, but it does NOT provide Duty Cycle %.

If you Produce/ Obtain any reliable data, please let us know. I presume the reference in the Thread Title to "fan relay" was unintended. As I'm sure you know, the Fan speed is variable based upon PWM Duty Cycle, as opposed to the older "On/Off" relay with NO speed variation. There IS a "Cutout relay", but that is ONLY to allow the Fan to run, if necessary, for several minutes AFTER engine shutdown to prevent Heat Soak.
George

[Daaaaaaaan]

Originally Posted by gbalthrop

That clamp meter can also measure DC Current (Amps) simply clamping a wire/cable, instead of opening circuit, particularly handy in Diagnosing Draw > 100 mAmp:
https://www.amazon.com/Electrical-Au...xpY2s9dHJ1ZQ==

And if you have the wire slack to do it, you can wrap the wire through the meter’s arms multiple times to get double,triple,etc readings if you need to measure something putting 50mA or 33mA through.

[shushikiary]

Thanks, I'm adding fans, not just replacing the stock one (extra coolers on the vehicle).

It wasn't that much more expensive to just get the derale 70 amp PWM controller they sell so I just got that.

I did find out that protools can tell the fan to run at 50% and 100%, so I could tell it to run at both those speeds and measure the PWM output with my hand oscilloscope.

[gbalthrop]

Originally Posted by shushikiary

... I did find out that protools can tell the fan to run at 50% and 100%, so I could tell it to run at both those speeds and measure the PWM output with my hand oscilloscope.

If you do that test, it would be helpful to those WITHOUT a meter that can read Duty Cycle, or without an oscilloscope, IF you would measure/ report:
1) DC Volts at 50% duty cycle, or whatever intermediate % trigger;
2) DC Volts at 100% duty cycle, or max % trigger.

I would expect an increase in DC Volts reading directly-related to Duty Cycle %. It would be helpful to folks without expensive tools if we knew approximate values of DC Volts/ Duty Cycle %. I have the Duty Cycle meter, but am too lazy to take mine apart to Test with meter & INPA.
Thanks,
George

[PhilJM]

No power to fan relay e90,2011
There is no power in the red/green line into the relay but cant trace that back to its source.
Fan works when bridging red/blue output from relay.
Any ideas?
Thanks

[gbalthrop]

Originally Posted by PhilJM

No power to fan relay e90, 2011. There is no power in the red/green line into the relay but cant trace that back to its source.
Fan works when bridging red/blue output from relay...

If there is NO battery voltage at X14188/1, Red/Green wire, with Ignition ON (Terminal 30G active), check fuse F28
on the JB Fuse Panel, visually & electrically. That fuse should have power when Ignition is ON & 30G relay is active. If Fuse
F28 is intact, with Battery voltage with Ignition ON, & yet there is NO voltage at X14188/1 with Ignition ON, then there is likely
an issue at X11003 on firewall side of JB, or in the Red/Green wire between X11003/8 & X14188/1.

If any questions about attached ISTA wiring diagrams, please ask.
George

[PhilJM]

Thanks George I will check those details out tomorrow and get back if I cant find a solution
Much appreciated
Phil

[PhilJM]

Hi George
No fuse in f28 when I installed one there was power and fan cut in.
Bigger problem maybe why there wasnt one I have only Had this e91 a month now.
Thanks for help
Do you know if there is a separate fuse for drivers side folding mirror as it doesn't adjust or fold and no motor sound ,the passenger side works fine.
Thanks in advance for any reply
phil