1993 JEEP YJ 1993 YJ WONT START NO POWER TO FUEL PUMP?

  • Tiny
  • Wrenchtech
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What we're looking for here is a 2 second pulse of "on" time. Your going to have to run all the same checks on the ASD relay and see if it is acting the same way.

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Tuesday, September 14th, 2010 AT 1:50 PM
  • Tiny
  • yjjeep
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Ran the same test on the ASD relay. Relay will pull in and output will light up. However I still have no response when I turn on the key-nothing.

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Wednesday, September 15th, 2010 AT 4:27 PM
  • Tiny
  • Wrenchtech
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I want to verify all the power or ground inputs to make sure they are working. It's starting to look like a bad ECM but I don't want you to buy one without someone else verifying it.

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Wednesday, September 15th, 2010 AT 4:38 PM
  • Tiny
  • Fyrbud
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For what it's worth.
Same Jeep, similar mileage. Will crank but not fire. Blower fan and windshield washers not working. Both Fuel pump and ASD relays have power to pin 30 for contacts, but neither has power to either side of their relay coils. Jumped contacts on Fuel pump relay and heard the pump kick on. Replaced ignition switch, no improvement. All fuses good, especially fuse #9 (Ign/lps) under the dash. FRUSTRATED.

Split the fuse block and started tracing wires. Manipulation caused turn indicators to work intermittently. Aha! More manipulation caused a couple of fuses to fall out. Hmmmm, I noticed the fuses were waaaaay too easy to pull out. Also found a blog where a YJ owner discovered JEEP MOVED THE IGNITION WIRE FROM IGN/LPS TO THE DOME FUSE in 1992 or 1993 without relabeling the fuse block. I removed the Dome fuse, cleaned the contacts and as I reinserted it I heard the fuel pump kick on. All the problems seem related to poor/dirty/loose contacts inside the fuse block. Twisting the legs of the fuse, just a little, seems to increase tension and conductivity. Pay very close attention to fuses #9 and #5 as one or the other supplies the power to the coils of both relays (and maybe the PCM module). Good luck!

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Sunday, April 19th, 2015 AT 9:14 PM

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