2002 S80 Idles, doesn't respond to anything

volvoforare · Post by **volvoforare** » 16 Sep 2015, 17:52

Dear Volvo S80 Forum,

I have a 2002 Volvo S80 T6 which was parked for a few months during summer. It ran perfect when parked. Now when I start the car again I have problems. It will start but run at an idle without responding at all to throttle. It’s not taking any input at all, so after a few minutes of running perfect it starts sputtering. Apparently the auto-choke changes and now the engine idles very poorly.
I ran Vida Dice and got the following error codes (see attachment of picture from Vida Dice):

CEM-1A62 Communication with ECM control module Signal missing
ECM-801A System relay – faulty signal

I removed the ECM and checked the contacts, and tried to clean them. No difference. The car will start but is not drivable at an idle. Can I have the ECM checked without the car? Any suggestions would be great. I was thinking some rat or other critter chewed on a cable somewhere (the car was parked outside) but there are really not many cables exposed from below.
Thanks,
John

: Picture from Vida Dice

I appreciate the feedback and have posted the initial state values below:

: Initial State When I ran Vida Dice again

I also have posted the Unselected CSC 2 values for this second run (and they are actually not identical).

: Unselected CSC 2 when I ran Vida Dice again

Thanks,
John

Post by **doublebug** » 17 Sep 2015, 00:29

Please post all errors from "Initial State" tab.

Post by **doublebug** » 20 Sep 2015, 14:24

You need to check power supply voltage that goes to A17 pin of ECM module (Power goes via fuse #6 under the hood).
If power is ok you may have bad ECM (ECM-711A Control module internal fault).
Also check FMA2 relay. Also under the hood.

volvoforare · Post by **volvoforare** » 21 Sep 2015, 13:54

Thanks for getting back to me! I checked fuse #6 and the fuse is good (zero resistance). The connector at fuse #6 read 10.2 Volts. I removed the ECM and identified the connector for the A17 pin by reading the bottom of the ECM. I found 0 Volts at that connector with the key in position 2. So this could be the whole issue? Do you think I can test this by running a separate wire from fuse #6 to the A17 connector?
I didn't check the FMA2 relay before removing the ECM but I assume I could swap FMA4 for FMA2 to test since they appear identical.
Thanks!
John

Post by **doublebug** » 22 Sep 2015, 01:16

without ECM connected you won't get power to the #A17 pin.
because this (FMA2) relay is engaged by ECM itself. ECM controls this relay by #B38 pin.
So you may test if there is good connection between #B38 and #4 pin on relay.
BTW 10.2 is small voltage. So that means your battery can be bad.

fartface · Post by **fartface** » 23 Sep 2015, 08:45

Hi doublebug, can you really reprogram a used erm? I have dice and want to make this unit work with mine, can you help me? Kirsty
My email is [email protected]

doublebug wrote:without ECM connected you won't get power to the #A17 pin.
because this (FMA2) relay is engaged by ECM itself. ECM controls this relay by #B38 pin.
So you may test if there is good connection between #B38 and #4 pin on relay.
BTW 10.2 is small voltage. So that means your battery can be bad.

Post by **doublebug** » 23 Sep 2015, 12:42

fartface, Why you want to replace ECM?

To tell if I can do that I need it's part number.