Radiator Fans not working

06 Jetta TDI. Replaced both fans and still not working. Scans show following Code:


Friday,17,September,2010,18:34:32:37720
VCDS Version: Release 10.6.1
Data version: 20100831


Address 01: Engine Labels: 038-906-016-BEW.lbl
Control Module Part Number: 03G 906 016 AB HW: 028 101 223 8
Component and/or Version: RC s01f EDC G000SG 7550
Software Coding: 0050071
Work Shop Code: WSC 66565 257 00032
VCID: 63C8A54BDB27
1 Fault Found:

006470 - Control Module 1 for Coolant Fan: Defective
P1946 - 000 - -
Freeze Frame:
Fault Status: 01100000
Fault Priority: 0
Fault Frequency: 6
Mileage: 261055 km
Time Indication: 0
Date: 2000.00.00
Time: 21:29:01

Freeze Frame:
RPM: 1260 /min
Speed: 18.0 km/h
Load: 35.3 %
Voltage: 13.83 V
Bin. Bits: 00001000
Temperature: 90.9°C
Duty Cycle: 9.7 %


Readiness: 0 0 0 0 1


Please help.

Do your fans work during the engine module OUTPUT test?

The link bob sent you is for A4 manual fans, not so good for BRM and later fans.

It sounds as if you have replaced the large fan with its control module (which serves both fans.) If that is the case then check for fuses and wiring issues.

I did not do a output test. Thank you for the suggestion. I will try this tomorrow. I did replace both fans. Do you know if there is a safety switch (trip) that turns off if the fans are under heavy load?

The ECU can and will turn off the AC if the engine is under heavy load (or thought to be under heavy load by the ECU.)

The fans can come on from high engine temperature, but this is very uncommon on a TDI.

If the fans do not come on within a minute or so of turning on the AC, then the AC high pressure sensor may not be functioning. What does your system pressure read in the AUTOHVAC module?

You can also read specified and actual fan speed in the AUTO HVAC module.

The code is telling me that the fans are indeed not coming on when requested, or at least that the ECU is not getting the expected feedback that they are coming on.

Fuse SA1, 200 amp metal strip, feeds SA3 50 amp red fuse. These should be on the front face (vertical) of your fuse block in the engine compartment. This is the motive power feed to your fans. Wire #1, 6.0 mm, red.

Fuse SA1, 200 amp metal strip also feeds J317 (main power relay ), one set of output terminals from J317 feeds fuse SB24, 10 amp (on the top horizontal face of your engine compartment fuse panel.) This goes through a wiring connection (A99), This is control power feed to your fans. Wire #2, 0.75mm, black. J317 (main power relay) is probably located on the top horizontal face of your engine fuse panel, and has a 458 painted on it.

There is also a main ground 642 from your fan controller that must be made up. Wire #4, 6.0 mm, brown. This goes to a ground connection "Engine Compartment, on top of left front chassis member". There are also two nearby grounds under the left headlight that should not be confused with this. Quote is from the Bentley.

The last of the 4 wires from your fan control module (located on back of main fan) is a communication wire to the ECU. This is wire #3, .75mm, green.

Thank you everyone for helping me. Ran an output test yesterday and the fans did not come on at all. Checked all the fuses except for the relays. At this point I am not sure what to do. I already ordered a Bently manual so that I could look at the wiring diagram. I am open to any suggestions. Thank you everyone.

DanG144, You are the man. thank you very much for your perfect advice. After $5.25 at the stealership and 50 amp red fuse, my car is as good as new. This is why we have this forum. So we can help eachother. Thanks again everyone.

Channa

Channa,
You are welcome. Save those old fans (if you have room), they may be ok, or at least have useful parts on them.

I edited my post, based on your feedback of fuse SA3 being a RED 50 amp instead of a metal strip.

Dan

Hi folks. 2012 Jetta issue.

I was having intermittent cooling fan operation, noticed by my a/c kicking on and off in city driving/red lights.

So i replaced the main large fan with new. seemed to work flawless for a day (probably coicidence) and im right back where i started.

I thought maybe i didnt connect the main electrical connector all the way so i jacked the car, pulled the lower cover off and right before i stuck my hand on the connector my fans randomly kicked on for the after-run function. I thought that was very odd.

Perhaps its the a/c pressure switch? as in the pressure had changed while it sat for 10 or so minutes while i was jacking the car and removing the cover?

any help would be greatly appreciated. I dont have a vag com and plan on getting some help later today but its not a guarantee i'll be able to do it.

You need to watch the refrigerant pressure data with a suitable scan tool.

A guess would be the RCV in the compressor though.

Oilhammer, that was all spanish to me.

I put the pressure gauge on the low side. its around 70psi with the compressor off, and with the compressor on its about 50 psi. WHEN the fans run, it will drop further to about 35-40psi.

but i cant get the fans to work all the time.

Climate is controlled by a processor, depending on your car's equipment it is either Climatic or Climatronic.... but they both are electronic, and compressor load and fan request is based off of what that processor sees from the pressure sensor.

You need a scan tool (such as VCDS) to access the Climate module and see these things. Otherwise, you are just guessing.

Im gonna try the high pressure switch today. I ordered one at napa this morning. Hope it does the trick. I'll still be trying to get a hold of a scan though.

Remove and replace until fixed can be a costly troubleshooting method.