2003 jeep grand cherokee. I have engine check light the codes i have are p1765 when i looked up the codes it said "Transmission 12 volt supply relay control circuit" . I don't really have a clue where ot begin. this economy has broke me. If any one can help.

SOURCE: Trouble code 54 on a 1995 Jeep Grand Cherokee

Carb'ed Engines:
Code 54 - Mixture Control (MC) solenoid is shorted or the ECM is faulty.

Fuel Injected Engines:
Code 54 - Camshaft (or distributor sync.) reference circuit - No camshaft position sensor signal detected during engine rotation.

Hope this helps

Mike

SOURCE: 2002 jeep grande cherokee check engine light

A common problem on many of the new cars is that when a person gets gas, they don't tighten up the gas cap. This will turn on the check engine light. Did you get gas recently? Another option is to see what code is stored in the ECU that turned the light on. This is done with a scanner tool. If you do not have a scanner, then have a dealer look at it.

SOURCE: 2005 Jeep Grand Cherokee Limited, 5.7L V8, starter

Every morning at lunch time and evening my jeep won't start. It doesn't grind but the electrical goes crazy. After a couple of trys it finally starts. Help

SOURCE: 2003 Jeep Vacuum Diagram

THERE SHOULD BE A EVAP/VACUUM DIAGRAM UNDER THE HOOD ON A WHITE STICKER. SOMETIMES THEY ARE ON THE BOTTOM SIDE OF THE HOOD ITSELF. I HOPE THIS HELPS. PLEASE KEEP ME POSTED THANKS FOR USING FIX-YA AND FOR AN HONEST RATING/COMMENT. GOOD LUCK

SOURCE: Jeep Grand Cherokee 2.7CRD (2004) auto won't change gear

check all the fuses before you do anything else. After all a fuse provides power to the electronic box that controls the transmission. Other than that I would not advice on a more complicated troubleshooting since there is no way for you to test a bad transmission computer, even mechanic shops don't know how to test them. The only thing they would do is slap a known good one and see what happens.