'00 S70 Uh Oh, ABS Issues?

[RussB]

Here's the low down. I leave work tonight, driving slow around several 90 degree left & right turns. On one RIGHT turn I applied the brakes and the ABS went off (made its ABS noise like when a tire skids) and both the ABS and STC idiot lights light up.

I shut the car off, and restart. STC light off, ABS light stays on until the system checks itself (around 10mph) Now all idiot lights are off.

I get on the highway after a 5 mile ride, and find I no longer have cruise control. It will not engage, no dash light. I try it in 4th and 5th gears. Nada.

I pull in my dirt driveway, and the ABS engages as I turn RIGHT and apply the brakes. ABS or STC lights DO NOT come on.

EDIT: Just read MattyMoo's ABS troubleshooting page. I did recently replace the front driver's side hub. I removed, cleaned and replaced the sensor. I'll make sure the axle bolt is tight. I also see a voltage fluctuation all the time. For instance, if I turn on the blower, the headlights will dim for a moment.

Looks like I have a lot of troubleshooting to do

[abscate]

It's really easy to break those sensor wires when you work on the hubs Russ. I just pulled mine a bit too much and separated the wire inside the sheath, no visual.

Once the ABS unit stops getting speed inputs from either wheel, cruise control on fly by wire cars gets disabled in software.

Easy to check continuity on the connector as it's nicely next to the shock towers...you don't even have to go underneath? 2000 ohms +_ 10% for an ABS sensor I think?

[RussB]

I was afraid of that...I also replaced the struts not too long ago


Just checked the battery & charging, all is well with 12.6v in the battery on a sub-freezing morning, and 14.65v while idling. That's all good

[RussB]

Damn, just checked resistance with my meter, one measures in the meg-ohm scale.


EDIT: did some more investigating. The actual sensor for one wheel is bad. The wiring checks out OK

[mecheng]

The front sensor's are relatively easy to replace. The rear is a bit tricky but I used a piece of string tied to the old sensor to route it properly. Ebay has some amazing deals, which I used for the rear sensor. 1yr in, and so far so good as the sensors are relatively simple.

[RussB]

I already pulled both sensors. One was fine, the other had a connectivity problem right where the wire enters the sensor. I peeled the insulation off the wire about 3" back from the sensor, and re-soldered the wiring harness to it. As long as the wires from the sensor are vertical, it seems to work. This a very temporary fix, the new one has been ordered

I was surprised at how important the wheel sensors are in an ME7 car. When shifting from 1st to 2nd it was as if the computer was cutting power to the engine. Even the idle was affected, as it wavered a few 100 rpm. As was already noted, there was also no cruise control

[abscate]

Lol!!!

https://www.matthewsvolvosite.com/forums ... ty#p383430

[RussB]

I missed your post first time around, thanks for the link. My new cable wont arrive till Monday, and rain is forecast. I hope my ghetto cable holds up!

[abscate]

YEah - the driving really sucks doesn't it?? It feels like you have forgotten to know how to use the clutch on a manual..

[RussB]

Indeed. Felt like a manual transmission rookie. I had the P1550 code as well