S40: Issue with ECC unit in V40

[ChristianJames]

Over the last few weeks I have been trying to solve a problem with my ECC system which one morning decided to pack in. The AC button LED flashes all the time now, the fan, and heater do not work and the heated rear windows seem to be stuck on even tho they are off. A relay under the drivers side near flasher unit sometimes clicks in sync with the flashing LED of the AC button (the air circulation button also flashes too insync if pressed on). So far in order to fix the issue I have replaced the resistor pack, tried anohter fan and had the ECC unit out with the PCB board on table for a close expection everything seems fine but i still got a cheap one off ebay to try in case it was the ECC unit but still no luck

which leaves me wondering what else it could be? anyone have any ideas? the other interesed thing that seems to have gone at the same time is the hazards don't work either if this is connected to the problem i dont know. The only thing i havent replaced is the blower relay which i think is the omron relay screwed near the blower?

Regarding the hazards ive replaced the switch and got a generic flasher unit to try fix it but niether of which worked, tho im not convinced the flasher unit was right and stuggled to find anywhere that sold the same type.

Would be really thankful of any help )

[littlehomer]

Good god.

What year is the car?

I'd check the wiring loom under the radiator for cracked and swelled wires and replace as appropriate.

You've obviously been through the basics of fuses etc. Check there are voltages at the right places like the blower etc.

The phase 2 heater controls have ICC chips on them, so a good look at the board might not reveal faults.

Could also be a temp sensor somewhere. But the hazard and rear window problem suggests not.

Again, if it's phase 2, might be linked to a CEM problem. I have a couple you can try if you like.

Cheers,

Daniel.

[ChristianJames]

Its a 1999 which is phase 1 I think? I will check loom as you said. Ive tested light sensor and the temp sensor in the ECC unit itself is good there is another one but im not sure of its location.

Would be good to have some detailed wiring schematic but I can only find the haynes manual ones which are far to basic to fault find.

Cheers for the help
Christian

[ChristianJames]

Sorry taken so long to report my findings:

Anyways - it was the classic fault of the loom and even more classic under the radiator.... well that must have been a major design fault!!

Turns out i found an amazing document online for the wiring diagrams for every part of this car 200 pages of nothing but electronic schematic etc.

So soon became clear what this issue was with both the ECC and the hazards not working, infact what i had not noticed was infact my cig lighter and parking lights where also not working... all these are feed from a Red 6mm cable from fuse box 11/A to fuse box 11/B via a phoenix connector labeled as F1 perect to unplug and meter from (Fuse box 11/B is under the driver side dash which is held in place with one nut and blot). I just re routed a new cable from the box 11/A job done.

For those who have had isses with their ECC or blower fan motor fuse 1 which is the larger 25a fuse feeds both the ECC and blower fan +12v via relay '2/8' so good places to check are 1. the fuse, 2 the relay (located on the 11/B fuse box its the left hand relay of the two that sit next to each other with the flasher relay centred under it). 3, if the voltage is getting to the blower (blue wire).

[twinturbo]

Originally Posted by ChristianJames

Turns out i found an amazing document online for the wiring diagrams for every part of this car 200 pages of nothing but electronic schematic etc.

Link?

TT