Mechanics

NO POWER TO PCM, NO CHECK ENGINE LIGHT,

1998 Jeep Wrangler

Electrical problem
1998 Jeep Wrangler 6 cyl Four Wheel Drive Manual 156375 miles

I just bought this Jeep with current issues. The Jeep will spin over fine, will display odometer reading in dash and show brake light and abs will go through normal cycle, but check engine light is not coming on and fuel pump is not working either. Also dont have any power to ingition coil when key switch is cycled on. I can't get the ASD relay to click when ignition switch is turned on and have swapped with other relays in hopes that was the case. I have checked for power at PCM connections with a test light and found that connector closest to engine has 12v on #1 terminal. Connector closest to fender has voltage at #3 terminal and when touched with test light and key switch on, ASD relay clicks on. But Jeep still won't start, and there is no spark at plug wires. Just so where all on the same page, I bought this Jeep with a locked up motor and the " lady" I bought it from replaced the water pump I'm assuming after she ran it hot. Then the motor seized up and she thought the battery was dead due to clicking sound, so she installed a new battery and still just clicked. So next she installed a new starter. Same problem. So, after I got it home, I pushed the Jeep down a hill and popped the clutch and got the motor unstuck, figured I could crank the bucket and hear it knock before I put a new motor in it, but I have to get this issue addressed before I start trying to install a new motor that still wont crank. I have checked all fuses and everything I know of has power in the dash and in the PDC.
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Mdantel
August 13, 2010.



Hi mdantel, Welcome to 2carpros and TY for the donation

No power to PCM, no check engine light,

Check and test fuse no. 6 30amp and fuse no.10 10amp

No.6 is the battery power to the PCM and no.10 to the CEL

I can't get the ASD relay to click when ignition switch is turned on-Could be the computer control of the ASD relay circuit-not grounding the relay

Rasmataz
Aug 13, 2010.
Are the fuses you are refering to both in the PDC or the fuse box behind the glove box?

Tiny
Mdantel
Aug 13, 2010.
The voltage gauge inside the car does not show any reading when the ignition switch is turned on. Don't know if that makes any difference, just a thing I noticed.

Tiny
Mdantel
Aug 13, 2010.