Hello friends.
First off there's cliff notes at the bottom for those who don't want to sit there and read my novel.

1994 f150 l6 300 automatic 2x4

Redoing my interior slowly but surely. Running into speed bumps every chance I get but that's life. Anyway, I upgraded to a cluster with tach off of ebay (my previous thread) And it runs wthout issues. I replaced all the cluster lights with LEDs to go with my color scheme. And just as I was putting the finishing touches before putting the cluzster and all the trim back in place I am now having ABS issues:
To start with, on the old tach the ABS light was continously blinking but there was never any buzzing and no issues braking.
Secondly, the parking light is never illuminated while the parking brake is engaged. The light works because it comes on while turning the key but otherwise is never lit.

Anyway, I turned the key to the "on" position and was deafened by the 3 series of 5 beeps, repeated when turning the key to "run" accompanied by a solid ABS light and again, no brake light.
I figured maybe being parked with the brake engaged for weeks had something to do with it. I disengaged tand reengaged the brake, moved the truck around etc etc with no changes I swapped the light bulbs around ensuring they werent an issue, also tried the incandescent bulbs. No results. Brake fluid level is good, rear brake lights come on.

Today I received my alligator clips and wiring and went to test the ABS port. Now, the ABS light comes on when turning the key, but comes back off, but is still beeing 5 times 3 times. Still no brake light.

I did the ground/unground procedure for ABS testing and "unfortunately" got the 16 flashes for all clear. I say unfortunately because now I don't know what the hell the problem still is. Any ideas? Would like to finaly be able to put this thing back together that's been taking up the whole driveway for weeks now.

Thanks in advance! and sorry for the wall of text, here's cliff notes

-replaced instrument cluster and installed LED lights and had truck parked with brake engaged for weeks
-old cluster ABS light always blinked but never any sound, never looked into it
-brake light only illuminates when turning key on old and new cluster
-started getting 5 buzzes 3 times and solid ABS light
-no more ABS light (still works as it comes on when turning key)
-still buzzing 5x x 3x
-tested the ABS port using ground/unground and received 16 flashes(no problem)
-brake fluid level fine, brake lamps all work, breake performance doesnt seem affected

Any ideas? Would rather not have to just pull the fuse

 

The beeping you describe is not the ABS but rather the airbag controller. It's trying to tell you that the airbag warning light circuit is open due to either a blown bulb, broken wire, or in your case the most likely cause is that you've got the wrong year instrument cluster installed and will likely need to re-pin the harness connectors or buy a cluster from a compatible year.

The brake light not working when the parking brake is engaged is likely the usual problem, where the switch on the parking brake pedal is not making good contact. Take it off, clean the contacts as best you can with some sandpaper, make sure it moves freely, and that should cure it. To test the brake warning light you could just ground the wire that goes to the parking brake switch, but with the wrong cluster in there you may not even get the brake warning light due to wiring differences.

 

I have to thank you. Reoriented the bulb in the airbag slot and I'm sound free. and now that I remember it was the airbag light that blinked in the old cluster not abs
Will get started on the parking brake

 

Great! Yeah the parking brake switch should be an easy fix. I've had to do it on every Ford I've owned! Glad to hear it was just a loose bulb and not an incorrect year cluster.

 

Can confirm. The airbag controller is beeping. In my case, PO put a 92 cluster in my 94. Your 94 can use a 94 or 95 cluster, but not 92 or 93. I'm not certain about 96 or 97 but I think they're also incompatible with a 94.

I swapped in a 94 cluster and had a blinking airbag light with a short to ground code. I replaced the clock spring to fix the short and my horn. Still had blinking airbag light. Swapped the airbag module for a junkyard one and all was good.

 

Just removed the switched. Pressing it manually didn't activate the light. But it came on when i grounded the wire. Guess it's yet another thing to buy lol. Now with the airbag light flashing do the flashes indicate issues? 5 flashes pause one flash pause 5 flashes repeat

 

Pressing it should DE-activate the light. It's a N/O (normally open) switch, where when you engage the parking brake the lever moves away from the switch and allows it to close, which turns on the light. See the two contacts that move apart when you press it? That is where you need to clean. Or just replace it if you'd like, should be cheap enough.

Yes the flashing indicates a code. In your case that is code 51 (5 flashes, pause, then 1 flash). What that means is that the internal fuse has blown on the airbag controller. Actually in our trucks it ain't a controller, it's called an Airbag Diagnostic Monitor if I'm not mistaken. All it really does is monitor the system, but it CAN prevent the airbags from deploying and that is what the code 51 is telling you.

The internal fuse is what's called a "thermal fuse" which means it blows when it gets too hot. Normally these are used to protect against overheating of electronic components but in this case it is used as a "self-destruct" feature where the thermal fuse sits on top of a resistor on the PCB (printed circuit board) inside the airbag monitor module. When the module detects a problem with the airbag system that could result in accidental firing of the airbag, it supplies current to this resistor which heats up and blows the thermal fuse, cutting power to the igniter circuit.

Which means... you likely have or did have more than one problem with the airbag system. The fuse being blown AND whatever caused it to deliberately blow the fuse in the first place. Below is a link to some info on how to repair this. It is for the Ford Probe but IF I REMEMBER CORRECTLY the codes are the same for our trucks and most other Fords of the same vintage. According to that thread, you only get Code 51 after the issue that caused the system to blow the fuse is resolved. So perhaps at one time you had a short somewhere and now it's gone and all you have to do is replace the airbag diagnostic monitor... or repair it per the instructions in that thread.

See here: https://forums.probetalk.com/showthr...p?t=1701278739

 

Forgot to say... I would check to make sure nothing is shorted before I got started on that code 51. Someone may have the relevant procedures from the shop manual to help you out. I will say this though: DO NOT connect ANY test equipment to the airbag itself, or to the deployment circuit while the airbag is installed. Ford makes this very clear in the manual. Connecting test equipment to the airbag igniter (part of the airbag module in the steering wheel) can cause it to deploy. Which can ruin your day if you happen to be in front of it.

 

Thanks for all the help man. I will look into all that.
While I'm in this thread, does it matter exactly which position the gauge needles are mounted in the cluster? My temp sender is bad. Coolant was way below N I grounded the sender wire and it came up to about halfway. I thought once grounded it was supposed to turn all the way?
Also, in the old cluster my oil gauge stayed in normal however with this new one it shoots to either Max or min. Oil is within range on the dipstick. I grounded what I think to be the oil sender and obtained the Same reading. Could it be a compatibility issue with my cluster even though everything else seems to work? Since grounding produced no different results is it possible the wiring coincidently went bad when I swapped clusters ?