Hello Everyone, having multiple helpings of humble pie today.
Can't figure out why the parking brake light is staying on. Brake fluid level is to the top, parking brake switch has been replaced, cable isn't stuck, parking brakes release, no uneven braking pull - I can't figure it out.
The only other thing that I've heard of is a bad level sensor in the master cylinder???

Anything else you can think of??

Thank you.

 

3 amigos on? Bad wheel sensor gives a hard fault that turns on the red brake light.

 

OK, didn't know that a bad wheel sensor would illuminate the parking brake warning light. I do have the 3 Amigos on and will address them tomorrow with a new shuttle valve.
Thanks, I'll dig into that as well.
Regards.

 

The BRAKE light always illuminates when the Three Amigos show up.

And I presume you're replacing the shuttle valve switches, not the shuttle valves. If you replace the shuttle valve switches without doing Option B you are most likely wasting your time. The switches themselves are very often not the cause of the shuttle valve electrical fault code. Go ahead and do Option B while you have it apart.

 

Yes, I am replacing the shuttle valve switches and will use the Option B.
Thank you!!

 

That's actually not correct, it is possible to have three amigos without the red brake light on, the brake light is on for three reasons:

1. Low brake fluid
2. Handbrake on
3. Failed wheel sensor

Typical three amigo faults like intermittent wheel sensor readings or the shuttle valve ground do not typically turn on the red light.

 

If you got the 3 amigos and the red brake light at the same time, I'd suspect just a faulty wheel sensor. I just had this exact issue last week. No lights and then all of a sudden the 3 amigos with red brake light came on. I scanned my abs system and found the rear left sensor was faulty. After replacing the sensor, all 4 lights went away.

If the red brake light came on some time after the 3 amigos were already present, then you probably have a bad wheel sensor along with something else (i.e. shuttle valve)

 

Brake fluid is and has been up to the top.
I did a continuity check on the hand brake light sensor and it was good. Purchased a new one, installed it, light still illuminated.
I replaced all the wheel bearing hubs that had the sensors with them about 6 months ago.

I am going to change out the SVS tomorrow (I know, I said that yesterday) and see what changes. May have to get a scanner to check the sensors.

Thank you,
Regards,

 

I stand corrected. Partly. But I was more correct than incorrect.

According to the brake warning light fault table in the RAVE, the only two conditions where the BRAKE light does not illuminate with the Three Amigos are a brake lamps relay fault and engine data anomalies.

I've never seen either of those fault codes mentioned in this or any other DII forum.

 

OK. I'll start with the SVS and go from there. I hadn't looked into the RAVE - probably need to do that as well into the future.
Thanks again - will keep the forum posted.
Regards.