Problem with Electronics, Transmission, Not Sure

[BlackVolvos70]

I have a 1999 s70 non-turbo Volvo that started acting up.

First, as I was driving I noticed that the speedometer would stop registering, the digital read-out for mileage and trip miles on the the speedometer dial would disappear and instead show doted lines, and the abs and brake warning lights went on. This would be temporary, for a few minutes, and nothing mechanical was awry. Then everything would return to normal. This went on for a couple days.

Then the condition became permanent for a day and suddenly the check engine light and a flashing orange arrow also displayed on the front display panel. As they appeared the Volvo would have rough acceleration at low speeds, taking longer to reach top speed and shutter at first. Now the check engine and flashing orange arrow appear on the front display panel.

I'm not sure all the events are related but they happened in a short time period and succinctly. It may be the speedometer cable or loose connections, the CPU, transmission, or something else entirely. Thank you in advance for your advice.

[JRL]

READ THE CODES

[CHI_S70]

Sounds like the ABS module. I had the same problem. Found a refurbished module on ebay for less than $100 and replaced it myself. Watch this you tube video:

Only problem is now I have the up-shift light flashing all the time. The repair took care of the ABS, traction control lights.

Anyone out there with further info would be greatly appreciated.

[Ozark Lee]

Part of the symptoms say it is the ABS module and then other parts say it is the electrical portion of the ignition switch. Both items are doomed to failure on all of our cars but the ignition switch is a relatively cheap part as is an ABS rebuild from Matty Moo or any of the other re-builders. They are both relatively easy to replace.

I'm not one to throw parts at problem but in your case I would likely go after both the ignition switch and the ABS module.

The only other thing I can think of is bad/dirty battery terminals. Those clean up for free so that might be a place to start.

...Lee

[BEJinFbk]

This sounds like textbook ABS module failure.
Should be no big deal.

You'll find very good info here:
http://home.earthlink.net/~vicrocha/

Your options are -
Remove and repair it.
Remove and have someone else repair it.
Take it to the dealer and get seriously ripped off...

[BlackVolvos70]

Everyone, thank you for your suggestions and I will try them all until something works, starting with the cables and ending with the codes if need be. I will let you know how it goes.

Ozark Lee, regarding the ignition switch. Earlier this year I replaced the key ring (for theft protection) on the ignition after the car would infrequently start. It seemed to have solved the problem. Could this have anything to do with it?

Thanks.

[BEJinFbk]

The ABS module provides the speed signal for every system in the car. Speedometer, Odometer, Cruise control, the transmission.
It even sends speed info to some of the higher end radios for an automatic volume control feature that's speed dependent.
If your ignition switch contacts were worn, or the cables were a problem, I'd expect other issues as well.
From your description, I'm highly suspicious of your ABS module. It all fits.

[BlackVolvos70]

So, a follow up question. While removing the ABS Module I stripped the lower left screw. Assuming there is no slick way to take the screw off I have to remove the brake control unit it is attached to. Is there anything I should be aware of and how do I bleed the system after re-attaching the brake control unit and brake lines?

Thank you.

[BEJinFbk]

I would make pulling the valve block an absolute last ditch resort.
Can you get a dremel cutoff wheel in there to take the screw head off?
A mirror may help. And lottsa light!

[Ozark Lee]

The bolts to the ABS module have nothing to do with the actual brake line system itself so use whatever means necessary to get them off. No brake bleeding should be necessary.

...Lee