t.loretto
NAXJA Forum User
- Location
- Vancouver, B.C.
Hey guys, i'm new to the forum and have been searching for weeks for an answer to my problem. I've got an 88 cherokee 4.0 with an AW4 tranny and it won't shift out of first gear. I did the manual shift test with the TCU unplugged and it shifts fine. I checked the TPS as per the service manual and its fine, and even put in a new one for good measure.
I did all the electrical diagnostics on this site: http://www.transonline.com/transdigest/magazines/1997-10/Shift Pointers/index.html.
Everything checks out except the brake switch shows 0.4v instead of 0 with the brakes off, the TCC solenoid has 21 ohms of resistance, and the TPS ground has 0.8v instead of 0.1.
But i figure none of those things should stop it from going into second, so i had a buddy probe the c15 terminal on the TCU harness (shift 2 solenoid) while i was driving, and the TCU wouldn't send voltage to it. It only sent voltage to shift solenoid 1. So i replaced the TCU with another and still the same story! I'm at my wits end tryin to figure this thing out, so I'm hoping one of you might have some answers.
Any help would be greatly appreciated!
I did all the electrical diagnostics on this site: http://www.transonline.com/transdigest/magazines/1997-10/Shift Pointers/index.html.
Everything checks out except the brake switch shows 0.4v instead of 0 with the brakes off, the TCC solenoid has 21 ohms of resistance, and the TPS ground has 0.8v instead of 0.1.
But i figure none of those things should stop it from going into second, so i had a buddy probe the c15 terminal on the TCU harness (shift 2 solenoid) while i was driving, and the TCU wouldn't send voltage to it. It only sent voltage to shift solenoid 1. So i replaced the TCU with another and still the same story! I'm at my wits end tryin to figure this thing out, so I'm hoping one of you might have some answers.
Any help would be greatly appreciated!