Abs light on, strange behavior

[94burbk1500]

Sorry if this is in the wrong place.

My 1994 k1500 suburban has the abs light on and if I hit the brakes with the wheel turned at low speeds the abs freaks out and pulses the brakes like crazy. I did pads, rotors, calipers, master, and booster recently, the drums were good, just needed some adjustment. I'm assuming this is a wheel speed sensor issue, but I don't have an ancient scan tool and would like some opinions before firing the parts cannon.

 

[fancyTBI]

It is in the wrong place. Perhaps the mods will be kind to move it to the “Axles + Brakes” section.

Rust on the mounting surface will cause the WSS to have incorrect readings. A damaged wire (rubbed through, broken, squished, etc.) can also cause this to happen. The FSM states that erratic behavior is usually caused by damaged wiring. Now that these trucks have some age on them it’s also become clear that the rust/corrosion on the mounting surface can also impact the sensor’s ability to read correctly.

Did any of this happen before your brake job? And how long have you owned the vehicle?

Is the ABS light on? You can pull the ABS codes by jumping the A & H(?) pins on the OBD1 port.

 

[94burbk1500]

It is in the wrong place. Perhaps the mods will be kind to move it to the “Axles + Brakes” section.

Rust on the mounting surface will cause the WSS to have incorrect readings. A damaged wire (rubbed through, broken, squished, etc.) can also cause this to happen. The FSM states that erratic behavior is usually caused by damaged wiring. Now that these trucks have some age on them it’s also become clear that the rust/corrosion on the mounting surface can also impact the sensor’s ability to read correctly.

Did any of this happen before your brake job? And how long have you owned the vehicle?

Is the ABS light on? You can pull the ABS codes by jumping the A & H(?) pins on the OBD1 port.

Yeah, this was happening before the brake job. I've owned the truck for 7 or 8 years now, it's got almost 200k miles on it and has spent it's entire life in states that hate car owners, aka salt on roads. The cv boots have been split for years, but I never used 4wd so I just left them like that. Probably just going to bite the bullet and do new cv's and hubs. I replaced most of the front suspension and steering components last year, might as well toss some more money at it. Haha

I didn't know you could get the abs codes, I've only ever had to jump pins to check engine codes once before. The light os on, I'll give it a shot. Thanks man!

 

[GoToGuy]

The front axle is not being powered by engine power, as your not in 4 wheel drive, but the half shafts, cv axles are connected to the wheels so they turn with wheel speed. Your not correcting, repairing the torn cv boots is setting up a disaster waiting to happen. What do you think happens after the grease is lost and the cv rotates at speed, metal on metal, all lube gone.

 

[94burbk1500]

The front axle is not being powered by engine power, as your not in 4 wheel drive, but the half shafts, cv axles are connected to the wheels so they turn with wheel speed. Your not correcting, repairing the torn cv boots is setting up a disaster waiting to happen. What do you think happens after the grease is lost and the cv rotates at speed, metal on metal, all lube gone.

I understand how it works, I put it off when I saw it then forgot about it. Disaster is a bit of an exaggeration though, the truck lives on a farm now, doesn't even see the road most months. I am going to replace them.

 

[fancyTBI]

I understand how it works, I put it off when I saw it then forgot about it. Disaster is a bit of an exaggeration though, the truck lives on a farm now, doesn't even see the road most months. I just said I was going to replace them, calm your ****.

He’s not wrong - unsealed boots let in all kinds of contaminants and can cause things to become un-lubricated and lock up causing additional failures. Don’t be so hostile.

 

[94burbk1500]

He’s not wrong - unsealed boots let in all kinds of contaminants and can cause things to become un-lubricated and lock up causing additional failures. Don’t be so hostile.

My bad, having a bad night and taking it out where I shouldn't.

 

[fancyTBI]

My bad, having a bad night and taking it out where I shouldn't.

All good. Hope you get this issue sorted. These trucks are worth the issues they seldom have. Take it easy man and hope tomorrow is better for ya!

 

[94burbk1500]

All good. Hope you get this issue sorted. These trucks are worth the issues they seldom have. Take it easy man and hope tomorrow is better for ya!

Thanks man. I love my truck, it's with me until it can't be fixed.

 

[94burbk1500]

Small update, I pulled the code, it's a code 6, erratic speed signal. The wires are intact, so I'm guessing it's a tone ring problem. I ordered new hubs and cv shafts for it. I'll let everyone know how it goes when I replace the parts this weekend.