ABS issues on front axle (possibly rear too)

[ReplicaR]

Hey guys, need some help troubleshooting the ABS issues. Here are some observations:

1. It seems consistent (locks up the brakes under heavy braking),
2. It's front axle only (possibly rear, maybe not enough clamping force to lock it up)
3. No warning lights on the dashboard

What are some of the steps, that I can do to troubleshoot it?

 

[cobrajeff96]

Both front brakes locking or just one?
Has any modifications been done to the brake system in general?
Usually any locking of the brakes indicates some kind of ABS component failure or overall system failure. The ABS light should briefly shine when the key is on, before cranking the motor. If it doesn't, the ABS module itself might be suspect.

 

[ReplicaR]

ANTI LOCK light does come on when the key is initiated into ON position. What's funny is that ANTI LOCK light is obstructed by AFR gauge pod on the steering column, so maybe I need to rethink that one. Might be a good idea to take it for a drive, and check to see which wheel locks up and then check if ANTI LOCK light comes on

 

[ttocs]

is it completely locking up and not going into abs or are you just pushing it hard enough that it is slipping and kicking the abs on?

 

[cobrajeff96]

WHen you turn key on with engine stone cold, do you hear a slight rattling/hum in the engine compartment? That's a sign that the ABS pump is priming its solenoids.

A good idea that costs you no money or time is to inspect each wheel sensor. To do it properly you ought to back them all out and make sure the actual pickup leads are still attached and to give them a good cleaning as they do attract ferrous metal. Bolt head is an E8 socket for the fronts and probably the rears too.

 

[cobrajeff96]

Also bear in mind there is a single ground hookup on the ABS pump body. It must be clean on both ends (the cable connectors (probably ring terminals) as well as the undersides of the bolt/nut securing them to their attachment points).

 

[ReplicaR]

So, here is what I've done so far. I've used the ABS testing port, and got the codes, which were the following:

• 41 - RF Wheel Sensor
• 44 - LR Wheel Sensor

So next step will be to order the faulty wheel sensors and rescan the system again, and then test it in real world.

 

[ReplicaR]

I've replaced the sensors, drove the car around, and tested ABS successfully. The code has changed to 12, which is an ALL CLEAR code