Tony302600 Posted February 14, 2008 Share Posted February 14, 2008 02 no start, no communication, 7.3L. Have power at DLC, all lights flash on the VCM, Have VREF ( 5.01v ) at MAP and EBP. Have all powers and Grounds at PCM, disconnected Fuel heater still same thing. The engine light stays on KOEO, Glow plug light stays on also all the time. The IDM relay clicks like crazy. Disconnect the IDM, still clicks, disconnect main engine harness still clicks...disconnect PCM...no clicks, but Glow plug light and engine light stay on. Customer said that on sunday in the bitter cold the truck didnt really have power...in the morning wouldnt start so he changed the Glow Plug relay and then when the relay started clicking like crazy and he finally gave up. With the glow plug relay disconeceted same thing. I have 12v on both primaary ( small ) terminals when conected on the GP relay. Any idea's? Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted February 14, 2008 Share Posted February 14, 2008 02 no start, no communication, 7.3L. Have power at DLC, all lights flash on the VCM, Have VREF ( 5.01v ) at MAP and EBP. Have all powers and Grounds at PCM, Exactly how did you verify this? disconnected Fuel heater still same thing. The engine light stays on KOEO, Glow plug light stays on also all the time. The IDM relay clicks like crazy. Disconnect the IDM, still clicks, disconnect main engine harness still clicks...disconnect PCM...no clicks, but Glow plug light and engine light stay on. Customer said that on sunday in the bitter cold the truck didnt really have power...in the morning wouldnt start so he changed the Glow Plug relay and then when the relay started clicking like crazy and he finally gave up. With the glow plug relay disconeceted same thing. I have 12v on both primaary ( small ) terminals when conected on the GP relay. That's because the PCM isn't grounding the relay circuit to turn the relay on. Any idea's? Put a breakout box on the PCM and check powers and grounds. When the IDM relay clicks constantly on an IH, it's a corroded power supply wire to the ECM. Good Luck! /forums/images/%%GRAEMLIN_URL%%/grin.gif Quote Link to comment Share on other sites More sharing options...
Tony302600 Posted February 14, 2008 Author Share Posted February 14, 2008 I verified powers and grounds by disconnecting PCM C175 and using a test light and voltage dropping them. Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted February 15, 2008 Share Posted February 15, 2008 I verified powers and grounds by disconnecting PCM C175 and using a test light and voltage dropping them. A test light does not provide enough draw for a proper voltage drop test. My test light only draws about .2a. Your test light could be plenty bright but the circuit could still not have enough amperage available to run the PCM. Do you have a 104 pin breakout box available? You've either got a power supply problem or a bad PCM. Do you have a known good PCM? I have one for a '99 that would work. PS I'll be driving to Milwaukee tomorrow for a 6.4 class Saturday. Should I go through downtown Chicago at 2pm on 90 and 94, or should I take the 294 bypass? Good Luck! Quote Link to comment Share on other sites More sharing options...
mchan68 Posted February 15, 2008 Share Posted February 15, 2008 The last 7.3L I had for a No-Start with a bad PCM, the "Check Engine" light would stay on when keyed on. Once the PCM was replaced, the "Check Engine" light would come on for a few seconds and shut off, if that helps. Quote Link to comment Share on other sites More sharing options...
Tony302600 Posted February 15, 2008 Author Share Posted February 15, 2008 Bruce....294 and 90/94 are THE WORST rodes to be on. It's hit or miss... I drove downtown on 90/94 at 3am... jam packed.. take 294... Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted February 15, 2008 Share Posted February 15, 2008 I know they're bad and that's why I asked. I was nearly killed as a kid in my parent's car on the Dan Ryan in a 10 car/truck pileup. My back still hurts from it..... My parents and family are from River Forest/Oak Park area. Thanks for the tip. /forums/images/%%GRAEMLIN_URL%%/grin.gif Quote Link to comment Share on other sites More sharing options...
Tony302600 Posted February 15, 2008 Author Share Posted February 15, 2008 Give you guys an update... Here i am.. /forums/images/%%GRAEMLIN_URL%%/banghead.gif /forums/images/%%GRAEMLIN_URL%%/banghead.gif /forums/images/%%GRAEMLIN_URL%%/banghead.gif Swapped PCM power relay...still same thing. Quote Link to comment Share on other sites More sharing options...
Tony302600 Posted February 15, 2008 Author Share Posted February 15, 2008 Ok, so i used a Fog lamp as a load to test voltage and ground on the PCM connector. Then i had no power from the PCM power relay to the PCM Connector.. Pins 71 and 97. Found the PCM fuse blown fuse 22. That fuse was good yesterday when i was double checking all the fuses. Replaced the fuse... everything is ok now /forums/images/%%GRAEMLIN_URL%%/shrug.gif /forums/images/%%GRAEMLIN_URL%%/scratchhead.gif.... I left the fuel heater unplugged when i got it running...then plugged it back in and still everything is ok /forums/images/%%GRAEMLIN_URL%%/scratchhead.gif. The only thing i did was disable the wiring from the alarm because it wouldnt turn off and the owner told me to. Quote Link to comment Share on other sites More sharing options...
Tony302600 Posted February 15, 2008 Author Share Posted February 15, 2008 Started running truck and it shut off....Threw a p0603. Reprogrammed PCM...then monitored pids....revved engine...then let it idle, ICP rammed to 4300psi and 4v... then through a p1209, p1211 what a weird truck. The IPR is on the CKT for fuse 22 that blew out of nowhere....maybe im lookin at one of those. On edit.... found wire chafing 2inches away from the IPR connector /forums/images/%%GRAEMLIN_URL%%/thumbup.gif Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted February 15, 2008 Share Posted February 15, 2008 This thread reads more like Tony's daily diary. /forums/images/%%GRAEMLIN_URL%%/grin.gif It's nice to get one like that fixed and on it's way with confidence that it won't be back for that concern again, good job. Quote Link to comment Share on other sites More sharing options...
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