ABS Motor / Power Steering Issue

[prsoto21]

Hey Guys,
I have a '98 Intrigue 3.8 engine. I was told my car needs a new ABS Motor due to the ABS and Brake lights illuminated on my dash. The hub assemblies were all replaced with Timkin hoping to get rid of these lights, however, it seems it was the ABS motor the whole time. My question is whether those lights affect power steering. Here is why and it's kind of weird.

When I turn my car on, there are no lights on the dash and when I put it into drive and pull out of a parking space the wheel is very smooth and easy. Then I drive 15 feet or so and there is scratching type of adjustment which I assumed is like an ABS Self test, and the the ABS and Brake lights kick on and the steering wheel becomes harder to turn, almost seems like I now have 50% power steering.

Ultimately I would like to know if the car is supposed to do an ABS Test after put into drive, and then if this relates to the power steering going away.

Any clues? Thanks in advance.

[LittleHoov]

I think its more of an issue with the Magnasteer system than anything having to do with your power steering.

Magnasteer is the variable assist steering on GM vehicles, it works as you described, it makes the steering wheel easy to turn at lower speeds and tightens the steering up as speed increases.

I am having similar issues with my ABS lights, etc, and have two new hubs that hopefully will fix my problems. What I did notice, is that when I left all the wheel speed sensor wiring plugged in, and the ABS had its problem, my Magnasteer stopped working, but I unplugged one of the wheel speed sensors and it works even though the ABS lights are on.

I guess what this means for you, is that you can try unplugging one of the sensors at the hub, be sure to somehow restrain the wiring so it doesnt get smacked by the wheel, etc. That might give you your magnasteer back.

What it means for me, is that my problem may be deeper than hubs. We shall see.

[BNaylor]

Originally Posted by prsoto21

Hey Guys,
I have a '98 Intrigue 3.8 engine. I was told my car needs a new ABS Motor due to the ABS and Brake lights illuminated on my dash. The hub assemblies were all replaced with Timkin hoping to get rid of these lights, however, it seems it was the ABS motor the whole time. My question is whether those lights affect power steering. Here is why and it's kind of weird.

Quite possible since both the ABS, traction control system and variable effort steering aka Magnasteer is controlled by the electronic brake and traction control module (EBTCM). The Magnasteer uses the front wheel sensors to change steering feel. Easier at low speed and then firmer at higher speeds for better road fell and feedback. The EBTCM controls the EVO actuator which should be located at the rack and pinion assembly.

What were the chassis/ABS diagnostic trouble codes?

[harmankardon35]

yes the variable effort steering is disabled as soon as the abs/trac off and SVS light kick on....I had a bad wheel hub in the front and the steering was harder to turn at low speeds...as soon as i fixed it the steering was good again.

[prsoto21]

Thank you for the replies. My mechanic never gave me any of the codes, which makes me suspicious. He originally said the scan told him the right rear hub was bad and it should get rid of my ABS / BRAKE lights on the dash, so he replaced it. Then he told me it was the ABS Motor up front on top of the hub. So another question is, Wouldn't the scan tool tell him that both were bad? Or is he giving me the run around? He told me they don't fix the EBTCM and to take it to a dealer.

At this point I might say the heck with it, apparently it's another $350 plus labor for the EBTCM and he said you need special tools, is that accurate? I thought I read in another thread you can take the module out, send it to a company to repair and then re-install. Anyone have any luck replacing the EBTCM by themselves, I'm fairly mechincally inclined.

[LittleHoov]

Im pretty sure its a dealer only part, but you should be able to get a used one for far less than the price of a new one.

To be quite honest Im not 100% sure what the ABS motor or EBTCM module is, but if I had to guess I would say its the "black box" with all the brake lines running out of it and the wires running into it. If thats the part, doesnt look too hard to remove, but youll have to bleed the brake lines afterwards. Im not sure about the special tools.

EDIT:
Ok, I thumbed through the Chiltons, not the best source, but all I could find without having to bust out the FSMs.

The ABS brake modulator appears to be the black box looking thing under the hood with all the wires running in and lines running out.

It does not have a picture of the EBCTCM module. But here are the directions for removal:

1. Locate the module under the instrument panel, to the left of the steering column.
2. Release the module from its bracket using the pressure tabs.
3. Detach the electrical harness and remove the module.
4. Installation is reverse.


I know thats about as vague as vague can be. To the left of the steering column and below the instrument panel is a fairly large area with a lot of wires running through there. I wish I could help more. The only other tidbit of advice I could offer is if youre going to go poking around the steering column and underneath with all those wires and stuff it might not hurt to take a few seconds to pull the Airbag fuse. Technically they can still go off even if the fuse is pulled, but Id feel better with it pulled personally.

[prsoto21]

Thanks again for the info guys.

My mechanic showed me where the part is, unless he is wrong. Under the hood and on the right side of the engine is a black box with the Delphi label on it. That's what he informed me of as being the ABS Motor. I'll investigate some more.

Thanks Again!
-Paul

[BNaylor]

The ABS motorpack aka ABS modulator should be the component with all the brake lines. Normally located under the area of the brake master cylinder. Depending on when your car was manufactured you could have a separate EBTCM module or it may be integrated into the ABS modulator/motorpack assembly. GM started doing this around the 1999 model years with the GM/Bosch ABS 5.3 systems.