I had been experiencing the common problem of the ABS/STC lights coming on on my 2000 S80 T6. I sent the ABS / STC controller out for rebuild, and upon reinstalling, the lights did not go out, but the check engine light came on when restarting a second time. I pulled a code of 1550 on my generic code reader. I can erase the code, but it reappears on restart. I think this code indicates no signal from a wheel speed sensor. How do I know which wheel sensor? Can I test these, without the Volvo VADIS? Are they the newer type of ABS speed sensors that you cannot check by just checking resistance? I've heard these newer ones are actually powered active components.

Could it have been a bad rebuild? I used BBA Reman, and I actually called them afterward, with my problem. They said that the code is now registering since the controller is now working, vs. before, it was not.

Thanks!

 

Have the ABS codes cleared.

 

Double check your connections on the ABS controller...

 

When I reinstalled mine several months ago I did not pull the little slide lock bars out therefore I did not get the hook up good Make sure that did not happen to you They are located on the side and you need to put them back inafter you hook up On My 2001 S80 I did not have to clear the codes they cleared themself after about 5 min of driving

 

Any update?

 

Thanks everyone. I'm going to check my connections tonight. I've already checked once, but I will again, as this seems to be the most logical problem. I opened the latch/hood on the connector, put the connector in the socket on the controller, and pushed down the hood, and it appreared to correctly "pull" down the plug into the socket.
Otherwise, I think I've got a bad wheel speed sensor.

 

I checked the plug, and it is fully seated. I also checked the wiring to each sensor plug, on the firewall (front sensors) and under the rear seat (rear sensors). All OK. Now, I just need to check each sensor itself, but how? I did read about measuring the voltage output as you turn the wheel, and I will try that this weekend.

thanks!