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Ever since I drove it home in February 2011 I've been having an intermittent ABS issue. Recently the ABS light has become more on than off, until finally permanently on. I've googled and read up on the forums.
Symptoms are as follows: ABS light is on all the time, which points at the relay. First I checked the wheel sensors all Ohmed at approx 1kOhm. One more indication that the relay is broken. Then I pulled the relay. It was a 944.615.119.00 part number. Odd. This isn't the correct relay, is it? It comes up at a blower relay when googled.
Anyway, I opened it, and it was broken. Physically broken. The little spring that gets pulled when the coil is energized, was literally broken in two, and randomly rattling around in there.
The relay I had differs from a generic relay only by a 1k resistor between the 85 86 terminals. So I got a standard cheapo relay and soldered in the resistor from my old relay. (What is it for?) Popped the relay in and started the car. ABS light on for a few seconds, and then it came out!
My car failed the bi-annual inspection due to the ABS light, so I instantly headed down to the testing station got get it approved, now that the light was out.
But as I was about to pull in to the testing station the bloody thing came back on!!!
It turns out the only thing being tested today is me
I guess I just have to do some more testing to figure this out.
There are also 2 relays in the drivers fender inside the ABS unit. You have to pull your fender liner to access the cover on the ABS unit. Now if you go to change that relay and talk to your local P-car dealer, they will want to charge you a load of money. Roger@928sRus has an alternative to it that I've been using with great success.
There are also 2 relays in the drivers fender inside the ABS unit. You have to pull your fender liner to access the cover on the ABS unit. Now if you go to change that relay and talk to your local P-car dealer, they will want to charge you a load of money. Roger@928sRus has an alternative to it that I've been using with great success.
Roger is on the case (at least I dropped him an e-mail).
I'll continue debugging shortly, thanks for all the input.
Relays at at the pump are ok, and i cleaned the ground there.
The relay at the ce panel works the opposite way of what I expected. The coil is energized with the ignition off, and the relay shuts off when the ignition is on. Is this correct???
Also I noticed the relay (when on) would shut off for a split second and then instantly come on again every 5-10 seconds.
What controls the relay? Just ignition on? And what does the relay do?
I feel the need to close this thread. A lot of noise from me here, I simply couldn't make any sense of anything.
The embarrassing truth is that I was measuring at the wrong relay position. I had the ABS relay mistaken for the relay that controls the radiator flap system ('87 feature only). So that's the reason for all the confusing info from me in earlier posts in this thread. Silly but true...
Roger airmailed me a new relay and one new sensor in record time, and everything is now working perfectly again.
All my sensors ohmed correctly, but one had a short to ground, and that was it!
So the lessons learned are:
-read the relay chart carefully
-ohming the sensors to approx 1kOhm is not sufficient to verify their health. Also make sure they are isolated from ground.
I The embarrassing truth is that I was measuring at the wrong relay position. I had the ABS relay mistaken for the relay that controls the radiator flap system ('87 feature only).
Don't worry about it. Learn from it. Update your mental procedures and keep on keepin' on.
I've made worse mistakes in the vicinity of the CEL (on my own car not clients' )
I feel the need to close this thread. A lot of noise from me here, I simply couldn't make any sense of anything.
The embarrassing truth is that I was measuring at the wrong relay position. I had the ABS relay mistaken for the relay that controls the radiator flap system ('87 feature only). So that's the reason for all the confusing info from me in earlier posts in this thread. Silly but true...
Roger airmailed me a new relay and one new sensor in record time, and everything is now working perfectly again.
All my sensors ohmed correctly, but one had a short to ground, and that was it!
So the lessons learned are:
-read the relay chart carefully
-ohming the sensors to approx 1kOhm is not sufficient to verify their health. Also make sure they are isolated from ground.
case closed
Been there putting the ABS relay in the wrong spot. Put the relay in the kickdown relay spot on a 5 speed car. NO start!
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ABS "fun"
not clients' 
)
