1996 850R Rear ABS speed sensor 9162612 Removal Volvo 850R - Sensor seized

[appropriatenoises]

I'm in the middle of (1st) cleaning, then probably replacing the rear ABS sensors on my 850R. I've searched and searched, and can't find the info I need.

I have spent the last hour trying to pull the rear ABS sensors out of the "hub" (for lack of a better name), and I can't get either of them to budge. I've (of course) removed the 10mm bolt. Anyone else have this problem? Am I missing something? Should they be sliding right out?

9162612 for 1994-1998

9472171 for 1999-2000 bastards

[Matty Moo]

They're a pain in the *ss. I wouldn't touch them unless I absolutely had to. Fronts almost always pop right out, even if they've been bathed in salt.

[nedro018]

use good quality "liquid wrench" product. let it sit for a day. drive the car to warm it up. apply again. let it sit for a day. then, when engine is cold, remove 10mm bolt, get a large screwdriver and start hammering lightly near the bolt pattern...try to break it free. the sensor -does- pull straight up. so, after you may have broken it free, use vice grips to toggle it straight up. use a little antiseize next time.

[appropriatenoises]

Giving liquid wrench a go as we speak. I know I can check resistance at the large connector to the ABS module for proper operation of the rears (which is why I'm troubleshooting/cleaning/possible replacing) My Resistance readings on the rear were:
Lrear: In the Mega Ohms
RRear: Open (no reading)

But can I check it right at the yellow connector in the trunk to rule out wiring problems elsewhere? Anybody know the pinout on the yellow connector?

Thanks!

[appropriatenoises]

Mark this one as resolved for any future unfortunate soul trying to sort out their ABS woes who have tried the ABS module re-solder to no avail.

1) I must be one of the 1% (those who's ABS problems are not due to the ABS module solder problem), because my ABS/tracs light was due to both of my rear ABS sensors being "dead" or open circuits. Confirmed by testing the yellow connector behind the back seat (pin 1 and 3 are one side and 2 and 4 are the other) New sensors installed and the ABS/Tracs lights are finally gone!

2) Removal of the rears: Matty Moo is right - a total PITA. And nedro018's suggestion is bang on. Lots of liquid wrench over a couple days and some heat with a heat gun and hammering as evenly as possibly maintaining the shape of the aluminum sheath. I ended up banging out the plastic (interior) of the old sensor, leaving only the sheath, which allowed me to get a large screwdriver inside the body of where the sensor was and bang it back. I also removed the E-brake adjuster and spring to give myself more room to work.

On to our next adventure!

[appropriatenoises]

Another Note: The Yellow Connector on the new sensor is a PITA to pull through behind the fuel tank and up to the hole where the fuel lines go. Here's how I dealt with it: I removed it and taped the bare spade connectors to the old sensor wires to snake it through.

- Cut the old sensors off their wires (helps with removal from the hubs anyhow)
- Remove the new yellow connector end:
1) Mark each wire as it corresponds to the number on the back of the connector using tape. I did this about 8 inches back from the connector, but you'll figure out a way to put them back in the right placement as you see fit.
2) Flip up the tab on the back of the connector (where the numbers are)
3) Use the end of a paper clip or a sewing needle to push the little tiny tab on the "top" of each "spade" connector (from the front) while wiggling the wire from the back, push slightly forward then pull the spade out.
4) Tape the new wires to one of the old ones and pull it through. You may have to break the clamp right behind the entrance to the fuel tank opening that holds the two fuel lines in order to free both old wires... don't bother trying to fit the new ones through there, just run them beside the clamp.
5) Re-assemble the new connector.

[abscate]

You can bang out the ABS sensors in the back by pulling the wheel and hitting the outboard face with a blunt screwdriver or dowel through the brake adjustment hole in the rotor/ drum combination. Ezpz

There is a nice picture in this thread - look with a flashlight to get the end of the black plastic ABS sensor in your sights

viewtopic.php?f=1&t=84246

[ZionXIX]

You can bang out the ABS sensors in the back by pulling the wheel and hitting the outboard face with a blunt screwdriver or dowel through the brake adjustment hole in the rotor/ drum combination. Ezpz

I sure hope they got it figured out within the last 5 years.

[RickHaleParker]

That's a job for DIY Penetrating fluid.

A 50/50 mixture of 100% acetone and dextron/mercron ATF.

Mix only what you need today in a spray bottle. This mixture has a short shelf life.
The two fluids repell each other like oil and vinegar so you have to shake the bottle well before spraying.

[abscate]

Patience is a virtue.

Ive been doing a lot of editing of threads, putting part numbers into title for easy searching, so when I find a good discussion of a topic, I just tack it on.