Abs And Tracs(?) Idiot Lights + No Cruise

[gr8gatzby]

Went on a 400mi roadtrip today and on the way home, while cruising at approx 75mph, the cruise control disengages. I look down to see the ABS light and what i think is the TRACS light illuminated. Its a small graphic of a car on a slippery road. Aside from the cruise control not at all engaging, the car is running fine, in fact she feels faster and my MPG has increased from a hwy average of 26mpg to 28.5mpg, noticed over the next 25+ miles. I did not pull the car over and continued incident free for the remainder of the 75mi home.

I don't know if it matters, but...1)my altitude on this trip ranged from 200ft above sea level to 6700ft. 2) i filled up with shell 93 50mi prior, 3) i was running low on gas about midway through the trip, so with only 2 gas stations in 600mi on the blue ridge parkway, i drove in neutral for the big downhill stretches, probably 10mi total in the Neutral position.

ideas?

[Seamus]

Your ABS control unit has failed. The cruse gets it’s speed signal from the ABS. The replacement is just like the 96 and up 850. Do a search in the 98 and below section to see how it is replaced.

[gr8gatzby]

everything is magically back to normal today. no idiot lights, cruise works...go figure

[rodrigo]

everything is magically back to normal today. no idiot lights, cruise works...go figure

get in touch with Viktor

[s70turbo1998]

everything is magically back to normal today. no idiot lights, cruise works...go figure

i would still get that looked at. i had the same issue where ABS and TRACS would come on, then the next day they would be fine, then another day it would be just ABS and it would "fix itself" two hours later. seamus is right, you're ABS module has failed as that was the diagnosis at the dealer.

[gr8gatzby]

ABS+TRACS cycled on and off again today. scheduled to go into the shop on Thursday. Is this normally a warrantied item? If not, how much should it cost to replace, and can I do it myself if not covered?

thanks for all the input.

[s70turbo1998]

this was not warrantied for me, i believe they only need to replace the ABS module, its apparently ~700 dollars for the part, since it was safety related my parents took care of that thank god. i wouldnt be the one to ask if its a DIY, im not that mechanically inclined.

good luck tho

[MarcS]

There is an alternative to the $700 replacement. There are a couple of rebuild shops. You can check out a couple of them here:

http://home.earthlink.net/~vicrocha/Volvo_...lvo_V70_ABS.htm

and here:

http://www.autoecu.com/Products/default.asp

I haven't used them yet. My ABS light comes on about every 150 miles and stays on until I restart the car. I pulled the connector and cleaned it (DeOxit, etc) and that seemed to help somewhat. I am concerned that I may have a wiring connector problem instead of an ABS one. In any case I am probably going to yank the thing and send it off to be tested/rebuilt and hope that helps.

BTW, When I talked to the dealer parts guy he said that he had 5 of them on order. In his words "That ought to tell you something" ie they fail frequently. I am surprised given the potential liability involved that Volvo is not more concerned about this!

[gr8gatzby]

i just spoke to the dealership and they said that no codes were stored, and that they are unable to duplicate the ABS/TRACS/cruise control failure, so they cannot fix what isn't broken. I get the feeling that they think that I am making this up, as the warranty is soon expiring(in 10k), and the fact that no codes were stored for either of the 2 instances that it occured, and the condescending tone....

can anyone here think of why possibly the computer chose not to log the intermittent ABS failure?

[garbergtsi]

you could have a ignition switch problem....

usually codes will store, and stay stored.

[connorb850]

If the light was on, a fault was present in the system and codes should be stored until erased.

[garbergtsi]

true....but not true.

the light can be on due to other things too.

dont listen to everything you hear on the intrawebb

[Vitor]

On 1999 and newer Volvos, the ABS system will erase the codes when the engine is started if the previous fault is no longer present.

Sometimes a hard fault is stored and it does not get erased when you start the engine; however, as you drive past 12 MPH, the system will perform a second self test. If the ABS light was ON and the fault is not present, the code is cleared and the light is turned OFF.

The intermittent fault is a sign (one of many) of a defective ABS unit. With time, the fault will show up more frequently until the speedometer stops working and the check engine light turns ON.

All the ABS control units (Installed on 96 and newer 850, 70 series and S80 models) will eventually fail after they reach 65,000 miles or 5 years. The average is 85,000 miles and/or 6 years for failures.

A dealer will charge from $60.0 to $120.00 to diagnose the problem and about 95% of the cases the mechanic will recommend to replace the ABS control unit.

Here's more information on this issue and a replacement alternative.

Vitor's Volvo ABS website

[gr8gatzby]

for 2 weeks now the ABS problem has not resurfaced since picking the car up from the dealer...even though they said no problem could be found....

go figure

[dang]

I had the same exact symptoms you are having. I even went to the dealership to have the ckeck engine light scanned. Just so happened that the code that came up was for the catalytic convertor (there was no problem with the CAT). Within a week or so, the CEL, ABS, TRAC, brake light all came on. It set a code for wheel sensors. I took the ABS module off and sent it to Victor Rocha and I haven't had a light on since. So, eventually, you are going to have to replace the module. Good luck.