1996 854 ABS light, instrument lighting

[Ozark Lee]

One other thing to double check is that the large connector got fully seated. It can fool you if the back of the latch doesn't catch the pins to draw the connector into the socket.

...Lee

[Teddy1975]

I have a feeling that it might be one or more of the ABS rings, I've forgotten the correct term for them, that might be at fault.

I've driven the car twice now after I resoldered the pins, and at engine start, the ABS light is on, then it turns off after the self-test (after 50 yards or so of driving). It turns back on after braking first time, although not instantly. When braking, the ABS kicks in even if the wheels are nowhere close to locking up and the brake distance is probably twice as long as it should be. I can drive on for about another 50 yards, then the light comes on and the ABS disengages for the rest of the trip. With the ABS off, the brake distance is what I would expect from a car of this size.

I hope the snow will clear soon, so I can raise the car, get the wheels off and have a proper look at the rings. Is it possible to inspect them visibly, without removing the brake disc or will it have to come off?

[PeteB]

I got our unit out today using the deep socket on a 1/4" drive wrench, it is so
tight that I had trouble getting two hands in there, really you have to try to
do it with one hand, once you crack them a turn or two they go easily by hand.
One was a bit frozen and made a loud crack when it finally gave.

I actually took it off before removing the connectors because I just couldn't
see them. I found out that you must remove the large connector first and you
just press down along the lower side that has the indentation, then the cover
rotates up and this seems to release the connector.

Once the large one is out of the way, then it is easy to see the two sides that
press release the other connector. The small one looks like it goes to the motor.
The wires in the large data connector looked okay, but the ones in the smaller
connector were cracked so that I could seen the conductors. I'll tape those,
even though it looks impossible for them to touch.

Post office was closed but I paid online and dropped it in the box to send it
to Midwest ABS for repair.

Are the circular things on the bottom solenoids to drive valves in the brake body?

[Ozark Lee]

Are the circular things on the bottom solenoids to drive valves in the brake body?

That is exactly what they are.

...Lee

[PeteB]

As I moved the connectors to put it back together nearly all the insulation broke
off of the smaller connector wires, so I had to tape them otherwise they would
have certainly shorted.
One more tip is to move the release latches on the hood hinges and put it all the
way up, provides a lot more light to make the job a bit easier.
ABS light is out everything is fine.

[Teddy1975]

Really glad to hear it worked out so well for you Pete.

In my case I got the VAG-COM cable and VOL-FCR 1.3. I can get readings from all the modules (those on my car of course) except for ABS. Vol-fcr says that it timed out waiting for response from car, that I should check if car ignition is ON and wait 3 seconds to try again.
Would this mean the module is dead or can it be rescued with resoldering?

[PeteB]

Thanks, did you remember to put the ABS fuse back in, I forgot it at first.
Also, are the connectors seated all the way?

[Teddy1975]

Sorry for leaving you hanging Pete, I have yet to be able to work on the car. As of now it is buried under 4" snow and outside temp is around 20F.

Next week we're supposed to be getting 40F temps, hoping at least some of the snow will thaw and I can continue the troubleshooting. I know I put the fuse back in, but the large connector might not be fully seated. That will be the first thing I'll check.

Thanks.

[Teddy1975]

Finally got the engine back to running (https://www.matthewsvolvosite.com/forums ... =1&t=74085) and was able to continue troubleshooting the ABS module.

I took it off and got it back in on the bench where I resoldered the pins and siliconed it back together. Installed it on the car, making sure fuse #14 was removed and put that back in after the install.

Moment of truth, started VOL-FCR and tried connecting to the ABS module. Lo and behold, communication established. There were 4 codes on the module, but seeing as those could have been from the bad soldering I cleared them and took the car for a short trip around the block. When I started the engine ABS went out. At 20 mph, ABS light back on.

Read the codes back in the parking lot and it now says ABS-322 Right Front wheel signal, extrapolation.

Seeing as I already measured all sensors to be within specified resistances, would that mean it's the ABS ring on the right wheel that's in need of replacement?