makehurst

I have a problem with my own car. I work at Toyota so only have there diagnosis kit but have my own snap on scanner. None of my cooling fans work. P0480 cooling fan 1 control circuit. New fans and controller, no broken wires. I have an always live and earth and an ignition switch and an ecu control signal. Used a scope on the ecu signal to the controller and have .3 volts. Activated the fans and nothing. looked more in to it and went to ecu long coding the snap on scanner said it’s a Skoda with a single fan a dsg box, my audi is a manual and My has two fans. Tried changing the coding and it won’t let me.
If I post my current coding can someone confirm it’s been coded correctly or not. I am assuming it’s had a second hand ecu fitted and not been coded in properly. And still got some of previous car stored in the ecu.
Thank you

SMac770

What is the car, model and model year? What is the engine in the car?

makehurst

Hello. It’s a a4 saloon Cjca black edition b8 2012

drgertol

So, UK market 2.0 TDI engine. Does your SnapOn diag tool report ECU information for the "01-Engine" address, e.g.:

(this from our 2.0 TDI CJAA engine). Funny that I don't find CJCA as an option for the 2012 European A4 in ETKA. --g

makehurst

hello
mine one is:
vag number 03l 906 018 ac
component r4 2.0l edc x25 2841

SMac770

Don't know why you'd jump to coding for an operational issue like that. Coding isn't something that just changes for the fun of it.

03L 906 018 AC = B8.5, CJCA, FWD, 6MT

What are your 1D_ and 8Z_ PR codes? 1D0 = no towing, 8Z5 = not hot country. 1D0+8Z5 for that engine, should be a single 400w fan. But if you are towing or mild hot or more, you probably have the 400w+200w fan setup. Even so, it's a single channel controller, that runs both fans the same.

The T5l plug near the terminal 30 distribution box (where the positive jump start post is) has the large term 50 line to the starter on it (red/black, pin 1), but then also smaller wires: power from fuse 11 to the fan controller (black, pin 2), PWM control from the ECM to the fan controller (red/white, pin 3), and, maybe, LIN bus to the voltage regulator (violet/blue, pin 4). Looks like the VR LIN line might be 2.0T only, not 2.0 TDI.

The problem is there's no specifications for what P0480 actually means.
16864/P0480/001152 - Ross-Tech Wiki

So you have a P0480, but what's the actual error code? An example from VCDS:
001152 - Coolant Fan Control Circuit 1
P0480 - 004 - Electrical Malfunction

Which is not that much more informative. But nothing about getting a P0480 gives any initial thought towards ECM coding. You have a straight issue with the fans or fan controller and just need to eval those components first.

If you do have the dual fan 600W controller:

T4bi plug:
1 - red, 12v from fuse in term 30 distribution block for fan motors
2 - black (maybe red/green), 12v from fuse 11 for J293 electronics
3 - red/white > green, PWM from J623
4 - grown, ground

You might test the voltage drop from pin 4 to chassis, might have a bad ground.

According to the diagrams, blue and white are the wires to the V7 larger fan and gray and yellow are the wires to the V177 smaller fan. You could run 12v direct to the fans and see if they spin.

makehurst

hello thanks for reply
my car is a twin fan set up. full code is
4527 coolant fan control circuit 1 p0480 00 [039] electrical malfunction
both fans and controller replaced as i was getting all the right signals to the controller so assumed bad fan control module.
the car is a 2012 but the date make on the ecu says 2019,so could of had a replacement ecu.
using a scope on the pwm to the controller the voltage never changed fans dont come on even though the ecu is saying running at 100%.
tested wires and all good.

edit

sorry just to add when you search the fault i find that others people with same fault, there fans run all the time, my dont come on at all
i even disconnected a engine temp sensor to see if the ecu panics and run the fans and nothing happened, also when i try to run the fans from my diagnostic tool

SMac770

Hard to say exactly how it's concluding the P0480 since it's not laid out in the Generic Scan Tool workshop manual. The ECM puts out a 12v PWM to the fan controller.

One would normally start by looking at the fan control measuring value, that's whatever the ECM is wanting for a fan duty cycle. Then look at the PWM signal and it either matches or doesn't. Then look at the fans, they are either matching in speed or not. You don't have to care about any inputs to the ECM since that's already boiled down to the fan control measuring value. You don't even need an ECM; just unplug it and put your own 12v PWM generator on the line to actuate the fan controller. PWM, it'll always be 12v, it's the duty cycle that changes.

Looks like CJC still uses a measuring blocks based ECM, not UDS like the EA888. Supposedly the group/block of interest is block 135, field 2 of 4 (or field 1 if you count from 0). The one with the % designation. There's also an output test for exercising the fan control. But again, you don't even need an ECM to really do that. If you just connect straight 12v to the fan controller input, that's effectively 100% duty cycle.