97 psd abs problems

[dunnc87]

This may not be the place to post this but hey, why not?

ok, so this truck has some issues. when i got the truck the brake pedal was very low, which i figured to be that the brakes were getting very low, however it was still driveable. About a week after i bought the truck the brake pedal went straight to the floor, no abs light, no parking brake lamp, nothing. So i got all new brakes, pads, rotors, hardware, drums, shoes, hardware and self adjusting kit, and a master cylinder. While bleeding the brakes the abs light has come on and WILL NOT go out. The pedal is up and brakes are all good. The pedal however is quite hard to push until about a half inch down then gets soft like a normal brake pedal. When sitting stopped it will kick back at you releasing the brake pressure. If you rest your foot on the brake pedal to where it just lights the stop lamps and turn the key to run, the abs light will come on shortly then go out as normal. let your foot off of the brake pedal and it comes right back on. do the same thing as you start the truck and it does it again, and the light will stay out as long as you have your foot on the pedal. as soon as you remove it the light comes right back on. the code from the abs module is 12 which means low brake fluid durng abs stop. I have checked everything and my boss insists that is this infernal rabs valve. but it is not a hard code. SOMEONE PLEASE HELP! this is driving me crazy and i almost cant take it anymore. thanks in advance and i know it is a lot to read. otherwise truck is great, love it so far!

[bob harris]

could be the ABS pickup on top of the differential

[BigFuel]

I like Bob's thought, Thinking that a pick-up sensor didn't get plugged back in or isn't sitting correctly to the gear (not touching the wheel but just above it). Also, did you bleed the ABS module? because of the way the valving works internally it may have trapped air in it. Happened on my Mustang.

[dunnc87]

thank you, i will check that. should i bleed the abs valve with key on or off?

[BigFuel]

Most people will tell you that you need a scan tool to cycle the ABS Module to bleed it but in actuality the system cycles several times (very quickly) when you rotate the key to the run position. Without a scan tool you need 2 people to do this. One person sits in the truck and applies firm constant pressure to the pedal. The other under the truck to crack the bleeder on each each front tire and one of the rears. When both are ready, crack the bleeder and cycle the key several times as the pedal moves forward. NEVER let the brake pedal go all the way to the floor. ALWAYS stop applying pressure about half way down and HOLD the pedal till the line is closed. On older trucks the front two brakes work independently from each other after the ABS Module (bleed both) but the rears are linked together so you only need to bleed one of them. Some trucks were lucky in that they even had a bleeder screw at the T-fitting on the rear axle.

Come to think of it my mustang has a bleeder screw for each wheel right on the ABS Module. It's a '97, check yours as well.

[dunnc87]

Why do I need to crack the front bleeders in order to bleed the rabs? That's the only abs I have is the rear...

[BigFuel]

Ok. Then just check the rear. I didn't remember if Ford waited till full disc brakes to go with 4 wheel ABS or not. The dealership I worked at for years was a bumper to bumper shop and things start to run together.

[dunnc87]

ha, thats alright. i was like hey wait a sec.. i dont have front abs... lol.

[dunnc87]

Update

so i found a leak at the abs module from the master in the line, so i replaced that and the wires on the abs module were saturated in brake fluid which i have read is bad, so i replaced the whole unit and followed proper bleeding procedure.

now when i hit the brakes and hold it the red brake light will come on until i let off then it will go off. i have no F***** clue with this thing and it is really pissing me off. someone please help...

[dunnc87]

The red BRAKE warning light is constantly monitored by the anti-lock electronic control module. If the red light illuminates, the anti-lock electronic control module will disable the RABS II system and turn on the yellow RABS light. For this reason, diagnosing and resolving any base brake concerns illuminating the red BRAKE warning light will, in most cases, resolve a perceived RABS II concern.


Brake Light Self Check

The red BRAKE warning light is used to indicate a low fluid level condition or parking brake applied condition. To check this light, insert the key in the ignition switch (11572) and turn it to the START position. The light should glow in this position. If it fails to glow, go to the Symptom Chart.

Allow the key to spring back from the START position to the RUN position. At this time the BRAKE warning light should turn off. If it does not turn off, recheck the parking brake to make sure that it is fully disengaged. In the event that the BRAKE warning light remains on, go to the Symptom Chart.

Where might i be able to find this symptom chart? or who may have it?