Well shit. I hope that doesn't mean it got ripped out of my trans harness.... because I don't see that plug down there in my harness.
Allison 5sp: Wiring issues... need help.
- Thread starter Jackblack99
- Start date
No man its all good! I appreciate it! Just ordered my pigtail so I can fix it. Thanks again to anyone that offered advice or help!
Got a couple of them out in the shop, or you should be able to pick one up from most any auto parts store. It's a standard 2 pin plug like GM used on most all of it's coolant temp sensors as well as many other switches.
Wish I would've seen this earlier, as I have 4 of them extensions! Dang it! I have a lot of random spare parts laying around FYI for anyone in dire need in an emergency. Usually
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Ok... not quite fixed.. wired the pig tail in quickly and plugged everything in... started it and no code for the speed sensor and no more "range shift inhibited" but the abs, brake and "service brake system" was on but no codes. I figured it was from when the vss wasnt hooked up. So I clear the codes and take it down the road.. shifts good, no lights or problems. Park it, route the harness correctly, hook everything back up and zip tie it all out of the way.. start it back up again and all the brake lights are back on.. but again no codes. Clear them.. go to drive it down the road again and CEL comes on won't shift out of 1st.. check that and get these codes P0748 and P0871. The brake lights never show a code and will stay off until I shut the truck off and start it again. The other 2 codes will clear and come right back.
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Check the ground under the drivers door? And brake fluid?
For the Trans codes I would look at that main harness since it's what you were messing with last. Unhook it and make sure all is well at the plug and nothing else got pulled on.
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For the Trans codes I would look at that main harness since it's what you were messing with last. Unhook it and make sure all is well at the plug and nothing else got pulled on.
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I found a green wire on mine( trans harness) up by the where the pinch weld on the floor board to firewall is that has been pinched. The coax wasn't tore but the wires inside where broke. It's gonna be a battle, but I will guarantee its a broken wire from tcm to trans. Also they have a tendency to rub the clamp on the power steering pump line. Check there as well as make sure it didn't jerk a pin out of either computer.
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Brakes work fine, the light just comes on. And I didn't have the brake system open and there are no leaks so it shouldn't be low. But I'll double check to make sure. I'll also double check the ground by the driver door. I just had it off when I ran the harness for the tcase because it had a ground that went there. And baddaddition I don't think it has anything to do with that. This whole problem started when the harness got tore up from falling into the drive shaft. I had the harness all apart a while back and ohm'd out the whole harness because of some wierd issues I had and it all came back good and my problem end up being a bad 12v key on power to the tcm and the tcm went bad. I just don't get why the brake lights keep coming on but I don't have any codes. Also I've seen guys post about bad batteries or low voltage causing similar issues... the truck was dead the other day when I went to start it, so I charged the batteries. Came out again a few days later and it was dead again. I had a red top sitting there so I tossed it in. It wasn't fully charged though but started the truck so I let it run for a few. Truck was dead again yesterday. I think my other battery is bad too.
Yea I will. Haven't had as much time as I'd like to work on it. Keep having machines go down at work and been working over a lot.
Update... checked the ground on the frame under the drivers door. It wasn't the cleanest so I wire wheeled it, cleaned both ring terminals and put it back together.. no change. So I started checking connections. Everything looked good until I got to the round grey plug on the right side of the trans... it wasn't fully plugged in.. so the codes were my screw up. But I also noticed the plug had a little trans fluid in it. So I'm going to order a new valve body harness and put that on when I put my new trans pan on. The brake issue is still there.. not sure what the deal is there.. still no codes.. so not sure what's the cause or where to go on it.
I double checked the fluid and the connection to the sensor on the master cylinder, all was good. Not sure what's causing the lights. Brakes function fine even the abs. Lights just come on after I shut the truck off and start it back up.
Check front wheel bearings, remove the abs sensor spray it with nrake clean and make sure the tone wheel down I side is in good conditions. Not ground down or rusty.
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