1999 S70 - ABS/TRACS/ENGINE LIGHTS - P1550

Pubcha · Post by **Pubcha** » 25 Nov 2014, 07:45

1999 Volvo S70 T5, ~250,000 km

I just finished replacing my passenger side wheel bearing/hub assembly. The bolts in my original assembly were terribly seized, so I also replaced the spindle which I got from a 1998 S70 (I had read that these parts are compatible, but maybe I am wrong). The 1998 assembly did fit perfectly in my 1999, except the speed sensor hole was a different size. However, the speed sensor in my 1999 was smaller and seemed to fit. I put everything back together and now my ABS/TRACS/ENGINE lights are on and I am getting a P1550 code. These lights were not on previously and I have no reason to believe the ABS was damaged during the replacement. This is why I think the problem may be related to the differing speed sensor hole size. Could somebody please help me with this? Should I be using a 1998 speed sensor instead? Is this not related to the speed sensor at all?

I am sorry if this has been discussed before. If it has, could somebody please send me in the right direction? Thanks!

Post by **Matty Moo** » 25 Nov 2014, 09:43

The holes are a different size and the sensors between the two are different.

I have no firsthand experience with what you are experiencing, so I can't say if the sensor and tone ring aren't aligning properly or the spacing between the two is off enough where it won't register properly. The only reason I know about this is from dealing with a guy a few years ago that had a car that was frankensteined together It was a 98 with 99 sensors and 99 knuckles. It only took me two weeks to squeeze that info out of him after he insisted that the car was completely original.

Pubcha · Post by **Pubcha** » 25 Nov 2014, 10:25

Thanks Matty. I could try and compare the spacing with the drivers side (correct) sensor. If I did put a 1998 sensor in (the larger one), would it be compatible with the 1999 system (ie. would the readings be similar in the 2 sensors)? Or would my car not recognize the readings from the 1998 sensor (or interpret them incorrectly)?

Post by **Matty Moo** » 26 Nov 2014, 12:27

I really don't know, I've never tried it.