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Q: 4x4 not working after many part replacements

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My 4x4 still isn’t working - I’ll explain… The GEM module has been changed, as well as the vacuum switch, selector switch, both relays, and I also checked the fuses. There’s still no power going to the switch and/or transfer case motor. Both the 4x4 light and the low range light come on when I start the truck. Is there another module behind the dash that I haven’t located that should also be replaced or is this a different problem?

A: The system would need to be tested for inpu...

The system would need to be tested for input and output controls from the GEM module. The GEM should also be setting a code for an internal problem. Once the codes are received, then a diagnosis can be done to locate the problem. If you need help gathering the codes, a technician from YourMechanic can inspect your car’s reduced power and assist with the appropriate repairs.

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