Last night i began to install my TruSpeed. Well i actually finished installing it, but it did not work. I had to find the ABS module, which was tucked down below the inner fenderwell, way up front behind the left headlight. I could not gain access to the plug, no matter what i did. I ended up removing the bumper, grille, both headlights and the headlight header panel, and i could not get to this. I ended up tracing the harness of wires that lead to the plug. There i found in the only gray/black wire, the one they said to tap into. I did not trace it to the plug, however it was the only wire of that specific color, so i tapped into it. Green to the plug and yellow to the loom, just like in the instructions. I started it up, and the ABS light stayed on. I proceeded to take it for a spin down the road and back, the speedometer DID NOT move. Tonight i hooked the power supply to another source, i even made sure 12v was coming out of the source, to the fuse. I even soldered the wire to the ring terminal connector on the ground. Still not working. I removed the battery and battery box, air filter again. I dug the harness back up, cut off both connections, triple and quadruple checked to make sure the wires were going to the right end. I cut off the old connections, and then made new ones. Hesitant to heat-shrink it, i started the truck up, still an ABS light. Speedo doesnt move still. Can anyone help me? Thanks in advance.

 

Check the power and ground at the TruSpeed module itself. Do this by carefully stripping away a little bit of the wire insulation from both the red and black wires on the module as close to the TS module as you can and attaching the meter's probes to those wires directly (I'm really hoping you're just using a bad ground). If the meter shows the module is getting power and has a good ground, then it's back to the ABS wires. Since I don't have a 7.3 I'm not sure if there's a difference in the way the fender liner and ABS modules are set up. On the 6.0 the only way to access the actual ABS module's plug is to come up through the wheel well by taking out a couple of screws where the fender liner attaches to the quarter panel (the 2 closest to the front of the truck), a screw and a push pin located up inside the wheel well, and then gently pulling the liner down a bit. Once you have the liner down you should be able to look-up there and see the plug. Keep in mind it's also possible (but unlikely) that you have a bad TruSpeed. Let me know.

 

Thanks. I was wondering how i could check for power into the module. So the positive goes directly onto the stripped red wire, and the negative goes right on the black stripped wire? I know i do have 12v power to the inlet of the fuse, but from there i am "?". I have had the problem of a bad ground on the assorted bolts under the dash, im hoping that is my problem. I hope i don't have a bad Truspeed. Thanks for the help Jon.

 

Just to be on the safe side. The best way to check to make sure that the module has a good ground is to attach the positive probe of the meter (I'm assuming your using a meter and not a bulb type circuit tester, those are bad) to a known 12v source and then connect the negative probe of the meter to the ground wire of the TS module, as close to the module itself as you can. Then do the same for the positive wire of the module. Attaching the positive probe of the meter to the positive wire of the TS module, as close to the module as you can and using a known ground to test. It would seem that if the speedo stopped working after you cut the gray/black wire that you got the correct wire in the loom, but just to be certain I would go back and check to make sure (or better yet have someone else take a look, just to get fresh eyes on it) that the yellow wire is connected to the half of the gray/black wire coming from the VSS and the green wire is connected to the side that is going to the ABS module. Also make sure that the module switch is completely set to either 1 or 2 and not stuck partially in between the 2 settings. You could also try resetting the module using the reset instructions.

 

Thanks, you have given me so much to go on. I would give you reputation but i have to spread it around. Im going to do this tomorrow after school/work and i'll get back to you. Thanks again!

 

I hope some of it helps. And if you come to find out you made a silly mistake, don't feel bad. When I installed mine, I got done soldering and was standing there all proud, thinking I was "The Man", because it was one the prettiest solder jobs I had done and I hadn't burnt myself like usual, when I looked down into the work tray and realized I had forgotten to slide the heatshrink over the wire before I soldered. So much for being "The Man".

 

Well, thanks for not making me feel bad. After doing as you suggested, cutting the insulation off a section of the wire, i had a good ground and a good 12v in. I even redid the connections for the green and yellow wires, even tried reversing them with wire nuts temporarily. Nope. Then i had the wild idea to check the plug. When i had the frontend apart to find the module, i found the plug, and i saw there was a slide in-out clip on the inside (towards engine) of the plug. I could see it with a flashlight, so i stuck it down there and pushed the clip back into place. Apparently the module plug was loose, and this fixed it. Reinstalled all the stuff, and went for a test drive. The calibration was off, and i had to fashion a skinny screwdriver with the grinder because that thing they give you just sucks. In the end i have it calibrated it very close, and im going to check later on this week with a portable GPS. Thanks for your help, knowledge like that can help in other electrical situations.

 

Glad to hear it's working. Now you'll have no excuse for speeding.