Code U0103 Lost Comm to gear shift module
Administrator
Joined: Apr 2010
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From: Clayton MI
I believe they are two separate modules..... I think as a first step, getting a set of factory service manuals for your car would be the best idea.... Chilton and Haynes are far to generic. Factory manuals are MUCH more comprehensive, and have wiring diagrams that actually resemble what's in the car. 
Registered User
Joined: Dec 2015
Posts: 10
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From: Central Oregon
Finally solved the problem
I started in the trunk and disconnected all grounds, hit everything with a wire brush, put some dielectric grease on, and tightened everything. Worked my to the front. Still the code would come up, usually after starting the car 5 or 6 times. Finally, pulled the underside of the driver's side dash apart. Started unplugging, spreading dielectric grease, and reconnecting all connections. Its been 2 weeks hasn't thrown a code at all. When it was initially throwing a code I had called and made an appointment with the dealership, that was last Tuesday. They checked for any codes and didn't see any, told me it must have been a bad connection under the dash.
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Joined: Dec 2014
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Okay I went to my car and started it. Tried to put it in gear and it would not let me get it out of park. The check engine light was on and it said it was in gear 8 which it doesn't have 8 gears. I had the car blocking cars in the driveway so I tried something. I disconnected the battery and reconnected it and it allowed me to drive the car. I drove it to Autozone and they scanned it. It pulled a Code u0103 saying Lost Communication with Gear Shift Module. I called our local Chrysler repair shop and they said it's either the Transmission Module or Powertrain Module. Apparently there computer terminology is different. My question is does anyone know the correct answer to the real problem??
Registered User
Joined: Dec 2015
Posts: 10
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From: Central Oregon
Check for any loose connections under the dash. Whatever connection you un-connect put some dielectric grease on the connectors and reconnect until they snap. Also, check all grounds, I brushed mine with a small wire brush put dielectric grease on and tightened the connection.
I had made an appointment with the dodge dealer when I first had the U0103 code come up. After reading other accounts of the code the same remedy came up - check the electrical connections. So when my appointment came up the dealership checked and didn't find a code (because I had used my OBD reader and cleared the code) but the mechanic confirmed that U0103 is a generic code and is usually a bad connection.
Its been over two weeks and no code and no check engine light.
I had made an appointment with the dodge dealer when I first had the U0103 code come up. After reading other accounts of the code the same remedy came up - check the electrical connections. So when my appointment came up the dealership checked and didn't find a code (because I had used my OBD reader and cleared the code) but the mechanic confirmed that U0103 is a generic code and is usually a bad connection.
Its been over two weeks and no code and no check engine light.
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Joined: Jan 2024
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i got 2007 Dodge Charger. there is code u0103 and the situation is while i drive the car , transmission stuck in a gear and doesn't shift anymore until i stop vehicle.
and every time when car is cold i start it it shows 8 next to PNRD on speedometer display.
please give me a favor if you had experience with it, i need to figure out what's the problem.
and every time when car is cold i start it it shows 8 next to PNRD on speedometer display.
please give me a favor if you had experience with it, i need to figure out what's the problem.
