1999 Audi A6 Brake Problems

Which parts fail

• Antilock/traction control/electronic limited slip › Control unit/module
  10
• Antilock/traction control/electronic limited slip
  9
• Antilock › Control unit/module
  3
• Power assist › Vacuum
  2
• Power assist › Hydraulic
  2
• Antilock/traction control/electronic limited slip › ABS warning light
  2

Components named in complaints (service brakes, ABS, rotors and pads, parking brake).

Mileage when the problem started

• Under 25k
  00%
• 25k–50k
  14%
• 50k–75k
  312%
• 75k–100k
  1454%
• 100k–150k
  727%
• 150k+
  14%

Owner reports

Selected complaints filed with NHTSA by 1999 Audi A6 owners, lightly cleaned up (personal details are redacted by NHTSA).

Two vehicles in front of my car on highway came to a stop; I applied brakes, pressing all the way to the floor of the car, and nothing happened - the car did not slow down and the ABS did not engage, despite there being loose sand and salt on the road surface. I rear-ended the vehicles resulting in substantial damage to my car (over $10,000 to repair) and the car I hit (unknown cost covered by my insurance company). My car spent 2 months in the shop having the accident damage repaired. When I picked it up, I tested the brakes and they were very "soft" - I had to press the brake pedal all the way to the floor to get the car to stop, even though I was going no more than 10 MPH. The ABS did not engage that time either. I returned the car to the dealer to fix the brakes. They kept it all day and told me that nothing needed to be done. …

All of a sudden my ABS light came on in my 1999 Audi A6, and the brake light started flashing. I had a full loss of my ABS brakes on icy winter roads. I eventually slid off the road and hit a fence. The ABS control module on my car had failed, and I've read posts of several hundreds other having the same problem. In my car it is a constant error, and no-one but Audi can fix the problem. I also contacted Audi, which claims that the ABS system disabling is not a safety concern. When there's a chance that your ABS (something you've relied on for years) suddenly shuts down because of a way too common error, it is a major safety concern. I was lucky I only got some dents to my car, but if Audi had recalled these I wouldn't have had to get repairs done to my car. Unfortunately someone will probably have to die before this safety concern is taken seriously and Audi will do a recall.

While driving 60 MPH on the freeway, the car accelerated on its own to 72 MPH as if going into cruise control. Confirmed the cruise control switch was turned off. Applied the brakes seven times. Car did not respond to braking. Engine seemed to race against the brakes. I put the car in neutral, moved to side of the road. Applied the hand brake. Turned key off. Car slowed then stopped. Since this incident the car was test driven twice by mechanics, during which it seemed to operate normally. On January 27, 2015 the car was taken to the local dealer, bellevue Audi, for diagnosis. Awaiting results.

(1) ABS/brake light indicators appeared on the dash. The amber (ABS light) stays on while the red brake light blinks. An audible alert sounds for 3 seconds, but the lights stay on. This indicates that the ABS control module is malfunctioning, thus loosing ABS abilities. (2) after researching through Audi forums (audiworld.com or audiforums.com), I discovered this is a common occurrence in Audi's (1997-2001), including a4's, A6's and vw passats. It is speculated that water or moisture seeks into the module computer board, thus shorts it out. It was confirmed by my Audi dealer that my ABS unit is defective. I received a $2,400 estimate to have it repaired. (3) nothing, too expensive- my bigger issue here is safety- most Audi/vw owners aren't aware that this is a recurring/frequent problem in their cars, because it's usually caught under warranty. …

Driving home tonight my car all of a sudden started accelerating (I drive an Audi A6 1999). Using the brakes I was able to slow it down enough to get off the freeway though my brakes seemed to be fighting against the car. I rolled through two stop signs as my car would not stop and luckily avoiding the other cars waiting there I was able to put my car in park and turn off the engine. I waited ten minutes or so and tried starting my car. The engine revved to 4 to 5000 rpms so, I quickly shut it off again. I waited again, tried it once more and the car started fine. I drove home, called the dealership and was told I could be seen on 02/14/11. Four days from now. This is the second time this has happened.

This is a problem that many Audi A6 owners have experienced. This occurs at random and the duration varies. While warning lights are on, braking performance is diminished as ebd is disabled and there is no ABS. Most owners including me have been told by the dealership that it'll cost about $2000 to fix the issue. They seem to be saying the ABS control module is the one that needs to be replaced. I feel since its a wide spread problem with this vehicle and it involves the ABS system which could cause an incident if one did not know the effects when they experience the problem; this issue has to be reported to the NHTSA.

Consumer received one of several recall notifications from the manufacturer, and took the vehicle to the dealer, who wanted for consumer to leave a credit card and then they will repair all defects, even those not related to the recall, and charge consumer additional expenses not in conjunction with the recall. Recall campaign NHTSA campaign id number : 01V157000 consequence: running out of fuel without warning while the fuel gauge indicates that there is sufficient fuel in the tank lead to safety problems. Vehicle ABS light was on.

Tl contact owns a 1999 Audi A6. The contact stated that the ABS module has been replaced numerous times. The instrument panel indicates that the ABS is not functioning properly. She stated that the axle on the driver side was replaced six times in three months. The dealer stated that the axle is too short. The contact stated that the parts have become very costly. The VIN, engine size, number of cylinders, and speed were unknown. The failure and current mileages were 58,000.

Intermittent ABS light displayed on driver's display. Problem is now continuous. Audi dealer ran diagnostic test and determined that ABS control module needs to be replaced. Relayed that this is a common failure item and unfortunately the cost for replacement is nearly $1000. Research on internet confirms that this is a common failure item for late 90's and early 00's Audi A6 models. Is there any information on a possible recall for this component?

It has become well known that the Bosch 5.3 ABS control module on Audi cars and other makes are defective and need to be repaired or replaced. A quick search on the internet reveals this fact. The control module on my 1999 Audi A6 recently malfunctioned repeatedly, meaning that I did not have to protection of the ABS braking system until it was replaced.

Related recalls

NHTSA investigations

Brake complaints in other A6 years