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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?

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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