Matthew Jeschke
Full Access Member
My buddy called me in a panic. I'm headed out there in a few days to help him rebuild the engine in his 1999 Jeep TJ. We think it has at least one cracked piston skirt. I should also mention this is his ONLY vehicle. He decided to do some diagnostic stuff before I arrive, specifically a compression test. Then he swapped around some spark plugs and wires. Not sure that's his issue.
He can crank the Jeep but it won't fire over. After chatting with him running through fuel, spark, etc. He mentioned fiddling with the Automatic Shutdown Relay to disable spark and fuel during his compression test. I suspect he triggered Chrysler's rollover safety switch and or key authentication circuit (key chip reader). Both of them activate what they call an ASD switch. This in turn cuts off power to ignition coil and fuel injectors.
I have the factory service manual and the dumb DUMB DUMB thing, says nothing about resetting the switch! I says something about a trouble light on cluster if key chip isn't read but no description of what it looks like. Not happy with Chrysler right now.
I instructed him to unplug the battery (reset memory) on control module. Didn't help. I think fuses are good as well as relay. I had him swap them around with known good ones. But Jeep still won't start. If still not working when I'm there in a few days I will use a power probe to better diagnose.
Any experience or tips in the interim? Anybody know much about late 90's Chrysler roll over switch aka ASD circuit?
He can crank the Jeep but it won't fire over. After chatting with him running through fuel, spark, etc. He mentioned fiddling with the Automatic Shutdown Relay to disable spark and fuel during his compression test. I suspect he triggered Chrysler's rollover safety switch and or key authentication circuit (key chip reader). Both of them activate what they call an ASD switch. This in turn cuts off power to ignition coil and fuel injectors.
I have the factory service manual and the dumb DUMB DUMB thing, says nothing about resetting the switch! I says something about a trouble light on cluster if key chip isn't read but no description of what it looks like. Not happy with Chrysler right now.
I instructed him to unplug the battery (reset memory) on control module. Didn't help. I think fuses are good as well as relay. I had him swap them around with known good ones. But Jeep still won't start. If still not working when I'm there in a few days I will use a power probe to better diagnose.
Any experience or tips in the interim? Anybody know much about late 90's Chrysler roll over switch aka ASD circuit?
