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We have been having an intermittent problem with our fuel pump not energizing. The last shop we took it to said someone had really messed with the wiring. They said they got everything cleaned up and working. 2 weeks later the pump won't energize. I have power at the fuse and relay however no power when it leaves the relay (BL/o wire). If I ground the brown wire the fuel pump energizes. Any ideas where I should start looking for the ground problem. I read the brown wire is for the PCM but can't find it's location.

Any help will be greatly appreciated.
 

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Welcome to Allpar. The wiring has to first be put back to what it originally was. Then diagnose why the PCM/TIPM isn't allowing the fuel pump relay to energize. Any alarm or security system option on the vehicle?
I don't have the service manual or wiring diagrams at hand. Are you able to toggle the fuel pump on and off with a scan tool? Any fault codes present in the PCM or TIPM?
I would only allow a Chrysler dealer service dept to service or work on electrical issues of this type. Most shops aren't equipped or are familiar with these CAN bus/TIPM systems. Any other electrical symptoms present?
 

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No, the only problem is the fuel pump. The only code is P0420 O2 sensor which I replaced. There is security or alarm system on the vehicle.
 

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There is a Dark Blue/Orange (DB/Or) wire from the fuel pump relay contacts that goes to the IPM (Integrated Power Module) to C1-34 (connector 1; cavity 34) of the IPM and comes out C1-33 of the IPM (same DB/Or color) to go to the fuel pump.
The Brown wire comes from the ground side of the fuel pump relay coil and goes to C3-37 of the PCM. C3 should be the 3rd PCM connector from the left and the Brown wire is in cavity 37.
The PCM grounds the fuel pump relay coil when it is safe to operate the fuel pump. The pump should energize breifly at key-on to prime the system and again when engine rotation is detected by the crankshaft position sensor.
 

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Make sure it´s not just a worn out pump..make a jumper and listen for the pump.
 
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