Kyle_Onyx

2000 XJ, 4.0

Turning ignition causes starter solenoid to engage but it instantly cuts all power and power cannot be restored by turning the key again. Have to remove negative terminal on battery and reapply in order to get power and try to start again. Tried to jump the starter to see if the problem was ignition or starter. Jumping the starter causes the same thing to happen. All fuses are good, relays are good, checked grounds and cleaned em. Battery and starter are brand new. Negative wire on starter had bare metal exposed and touching engine block, i wrapped up in tape and problem still persists. There is something forcing a complete electrical shutdown when starter is engaged.

The only code that the jeep has is P0740 which is Torque Converter Clutch Solenoid Circuit.

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Does anyone have any experience with a problem like this? Does the code and my problem have any correlation? Is PCM commanding a shutdown because of a potential electrical issue in TCC? To me, these 2 have no relation, but im open to ideas. Anything yall got is helpful.

Jim Malcolm

It sounds like your negative battery cable needs replaced. They corrode internally under the insulation and it usually shows up as "it works if I move my battery terminals to get a better connection". The TCC issues could very well be causes by the battery cable issue.

awg

examine battery terminals, cable ends, clean up everything with file or grit, go again

If still no good, you can verify by jumping bat neg as well (in theory)

frayed, taped up cable is a fair indication replacement is needed

You can make them yourself, have them made, or order, Rock Auto would probably have them

The stock ones are one size too wimpy imo, some bean counters cheapout

Kyle_Onyx

Removed starter and did some electrical testing with various grounds and wires. The problem ended up being the negative battery cable not providing adequate ground to the engine block where its mounted, therefore not providing ground to the starter. Many more hours of tweaking saved thanks to this solution. She cranks over now. Now to fix the mechanical issues!