ABS Light 02 Park Avenue

[sirgeoff]

I just purchased a 02 PA, 45k miles and failed the inspection process. The test identified that my emmission was a problem as well as the ABS brakes (ABS will not go off). The car was sitting for six months and I was told the brakes were just done. I'm speculating that the person who performed the brake job damaged the sensors. How do you inspect the sensor and why would an 02 vehicle fail emmsion? The Service engine light came on just once within the month.

[Bassasasin]

I hope this infomation is good.. Your car is a newer car than mine and I was just wondering.

If you drove your car soon enough to an inspector I would suspect if it has had time to re-learn itself. Especially if the battery had failed or lost its charge in that 6 mos. or something. In that case you might try driving it a bit. 45K miles isnt that much driving on an average O2 sensor but replacing a poor one will definately give you better results in gas mileage.

The O2 sensor tells the ECM how to control the mixture. It may be loose, damaged or just be wrong info.

If you feel like getting your hands into it, check for stored codes and clean your MAF sensor is a good realatively easy start to helping your emmissions. I hope the O2 sensor on a 02' isn't too bad of a swap but they will cost. My model is around $50.

Also Im working through an ABS problem right now.. have a hub sensor assy on order.
Luckily I found a wheel sensor on my right front not measuring 800-1400 ohms.. actually it was an open. Seems popular ABS problems are wheel sensors.
They can be measured at the connector on the wheel or at the ABS control connector to the unit across the correct pins. You could do a visual check to see if on of the sensor wires has somehow gotten loose, damaged or disconnected.

Also, I hear from this forum using an impact wrench in that area can damage a sensor and some sensors are still bad if they measure good.
An ABS diagnostic tester would do a much more complete job. It will actually look for those sense pulses and diagnose them, but shops around here charge $50-85 for the setup and diagnosis and rightfully so, considering their investment and expertise.


Good Luck.. Keep us posted.



Good

[sirgeoff]

The resistance measurement is done across the connector? Where is the connector located; directly on the caliper? Also, you also mentioned impact wrench. Would that vibration include lug nut removal as well?

[Bassasasin]

Dont know bout an actual impact wrench incident but it was advised as a risk from the forum. Personally I dont think lug nuts would be a problem since the mass of the tire absorbs alot of shock and we would see lots of problems with lots of ABS systems anywhere.
Without the tire an impact has much more effect.

Yes measure across the 2 pins on the connector at the wheel Or across the pins in the chart I will post below. Hope yours is the same.
There is a big connector on the BCM, for the front wheels one inside the engine compartment on the wheel well and a last one just outside the wheel bearing hub with a 6 inch pigtail.. I never made it to check the rears connectors since they bugged good at the BCM

I measured at the BCM first, found the bad wheel and bugged down to the one on the wheel determining it was my Right Front wheel.

For me the Large connector at MY BCM was easiest. Here is the pins on mine.
94' buick BCM connector
PINS 800-1500 ohms
48-30 LHFront
47-29 RHFront
46-28 LHRear
45-27 RHRear

Good Luck

[sirgeoff]

Thanks for the explanation and detail. I'm expecting to see my Shop manuals arrive by next week. I may decide to review the technical manul a bit before taking a go at it. I'll post my results most likely in a week. Thanks again!

[82Stang]

In my own personal experience, an ABS sensor tends to be a wheel sensor....which in case is usually the wheel bearing hub assembly. These darn things are expensive, but I recently replaced one on my wife's 99 Park Ave and sure enough, 3 months later I got scanned and it was that wheel sensor. After using warranty, I got a new one and it was indeed the same wheel. There was nothing I did different, just new part. The code was gone. If this sounds like you then, the same may also me the case. Just thought this would help.

[Bassasasin]

OK Just put my hub/sensor assembly in..

Took off the wheel.
Put it in Neutral with both wheels off the ground and car in neutral so I could turn the hub. Put a drift pin in the brake disc vane and spun off the axle nut 33mm. Tough. Theres one larger hole in the hub to unscrew the screws out and used a Torx to unscrew them. Very tight little buggers.
Then it was a punch that started working it off the assembly.
The axle was there but worked out of the way when needed. No problem.
The old hub came off and in pieces. The sensor came apart and had to punch out the remaining ring and sensor pieces from the backside.
Then reversed the process.
ABS light went out.. Im happy..
took me an hour or so.
Part cost $120. But im safer now and winter and slick streets are comming.

Good luck to all