bgblk1968 Posted September 25 Share Posted September 25 Wasn't sure where to post in electrical or fuel related. Truck came in will not run. Customer had changed ecm, fuel supply pump, and anything else they could replace. I checked fuel pressure running on starting fluid for a few seconds and it was good. No codes except (when it does run on starting fluid) it will throw every unit pump code. No exhaust smoke. I did change flywheel and cam sensors. It's getting rpm signal when it goes in crank mode. Would a single unit pump shorting out cause this? Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/ Share on other sites More sharing options...
fjh Posted September 25 Share Posted September 25 Crack at least three fuel lins At the head pump the hand primer till you have solid fuel NO FOAM then tighten and then try to crank it should light up on those cyl enough to get running provided there isn't an electrical glitch! 2 Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559021 Share on other sites More sharing options...
Joey Mack Posted September 25 Share Posted September 25 check fuse #40 in the engine fuse box. check the big ground bolt in the block in front of the starter. theres more, get back to us.. 2 Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559025 Share on other sites More sharing options...
bgblk1968 Posted September 30 Author Share Posted September 30 Pure fuel when pumping. Still will not pick it up. I've check Fuse 40 and now have fuse box off looking at backside wiring. Fuse is OK, but cover been missing so not great shape, but should work. All grounds loosened, cleaned and rechecked. Pull nozzles out and sent to fuel shop just to see how they were popping. Decent, but nothing to stop from cranking. Possible to set up some type light to see if unit pumps are firing? Seems like I'm overlooking something really simple. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559285 Share on other sites More sharing options...
Joey Mack Posted September 30 Share Posted September 30 check the condition of the RPM/TDC sensor in the flywheel housing, and be sure to inspect the wires upstream as far as you can reach, those wires take a beating. also check the Eng.Pos sensor in the front cover. there may be a teardrop shim installed, remove it and put it in your pocket and try again. To a few here I sound like a broken record, but have done this many times. check the ohms on the sensors, I think its 900-1500 at 70 degrees.. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559292 Share on other sites More sharing options...
Joey Mack Posted September 30 Share Posted September 30 is this an ASET-I or CEGR? ,, truck model name will tell me if you dont know 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559294 Share on other sites More sharing options...
bgblk1968 Posted October 1 Author Share Posted October 1 2005 Mack CXN613 AC-427 ASET Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559349 Share on other sites More sharing options...
fjh Posted October 1 Share Posted October 1 4 minutes ago, bgblk1968 said: 2005 Mack CXN613 AC-427 ASET so is it still throwing up codes? Long shot here ! How ever Unplug the wiring from the engine ECU and check for oil or coolant in the plug! 2 Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559350 Share on other sites More sharing options...
Joey Mack Posted October 1 Share Posted October 1 When i get home i will post the pin out diagram for the EECU. just in case you try to chase a wire.. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559362 Share on other sites More sharing options...
bgblk1968 Posted October 1 Author Share Posted October 1 Please. Send any diagram! What should unit pumps ohm without any wires hooked to it. If one unit pump went bad would it cause all not to work? Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559368 Share on other sites More sharing options...
bgblk1968 Posted October 1 Author Share Posted October 1 fjh I have nozzles out getting checked and will let you know when i reassemble. Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559369 Share on other sites More sharing options...
Joey Mack Posted October 1 Share Posted October 1 1 Bad EUP. Wont affect the others, the wire harness is known to crack right behind the EUP's and rub the block. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559370 Share on other sites More sharing options...
Joey Mack Posted October 1 Share Posted October 1 https://photos.app.goo.gl/gpWxfZcKcdhLiXp66 My new phone doesnt let me post pictures, so here's a link. it is several pin-out charts.. for ASET-CEGR Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559378 Share on other sites More sharing options...
TechTy28 Posted October 2 Share Posted October 2 On 9/25/2024 at 4:32 PM, Joey Mack said: check fuse #40 in the engine fuse box. check the big ground bolt in the block in front of the starter. theres more, get back to us.. Joey I've got a 1999 ch613 that won't start. Will start by jumping starter from hot post to key switch wire and will start if I remove VCU fuse. I'm from an International dealer and don't know these trucks very well. You seem to know them extremely well. Any ideas? Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559415 Share on other sites More sharing options...
Joey Mack Posted October 2 Share Posted October 2 Have you pulled the kick panel on the right side to inspect the wires for the VECU? T-27 torx, theres a row if screws under the edge of the floor mat.. Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559416 Share on other sites More sharing options...
TechTy28 Posted October 2 Share Posted October 2 2 hours ago, Joey Mack said: Have you pulled the kick panel on the right side to inspect the wires for the VECU? T-27 torx, theres a row if screws under the edge of the floor mat.. Yes. All wires look good and tight. I pulled RPM sensor and it has zero resistance. Would that cause a no start? Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559419 Share on other sites More sharing options...
Joey Mack Posted October 2 Share Posted October 2 Zero resistance... Should be between 900-1500 if memeory is correct 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559422 Share on other sites More sharing options...
TechTy28 Posted October 2 Share Posted October 2 5 hours ago, Joey Mack said: Zero resistance... Should be between 900-1500 if memeory is correct That's what I'm asking. Would that cause it to not start? Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559449 Share on other sites More sharing options...
JoeH Posted October 2 Share Posted October 2 On 9/30/2024 at 3:54 PM, bgblk1968 said: Pure fuel when pumping. Still will not pick it up. I've check Fuse 40 and now have fuse box off looking at backside wiring. Fuse is OK, but cover been missing so not great shape, but should work. All grounds loosened, cleaned and rechecked. Pull nozzles out and sent to fuel shop just to see how they were popping. Decent, but nothing to stop from cranking. Possible to set up some type light to see if unit pumps are firing? Seems like I'm overlooking something really simple. What's your battery voltage when cranking? EECU shuts off around 9.5 volts. If your batteries or electrical system is causing a drop in voltage at the EECU then it can't start. I've been lucky enough a couple times to get my 2003 to fire up with minor assistance of ether in this condition when I let off the key the EECU powers up and takes over. Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559455 Share on other sites More sharing options...
Joey Mack Posted October 2 Share Posted October 2 it can, but usually a hard start. it works with the eng. pos. sensor in the front cover. that one reads the cam.. I would replace the flywheel sensor, and look at the front sensor. if there is a teardrop shim on that sensor, put it in your pocket and put the sensor back in. the sensor should have 774-996 ohms resistence at room temp. up to 1300 if a bit warmer.. Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559456 Share on other sites More sharing options...
Joey Mack Posted October 2 Share Posted October 2 I know you are at an Int. Dealership, but if you get a steady diet of 98-2006 Macks, this book is valuable... 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559457 Share on other sites More sharing options...
TechTy28 Posted October 2 Share Posted October 2 1 hour ago, Joey Mack said: I know you are at an Int. Dealership, but if you get a steady diet of 98-2006 Macks, this book is valuable... The sensor wad bad. I replaced it and it took care of the blink code but still won't start unless I pull 10 Amp VCU fuse in the dash, pull fuse fires right up then shuts off in a few secs but if I reinstall fuse as soon as it starts it keeps running fine. Idk Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559459 Share on other sites More sharing options...
TechTy28 Posted October 2 Share Posted October 2 Also this is a truck I will continually be working on so I am going to try and find that book somewhere Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559460 Share on other sites More sharing options...
Joey Mack Posted October 2 Share Posted October 2 has any wires been repaired or tapped into on the data link port above the throttle pedal? IE: E-Log....? Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559462 Share on other sites More sharing options...
fjh Posted October 3 Share Posted October 3 Did you check the engine ecu plugs for coolant push? 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74581-2005-mack-aset-will-not-run/#findComment-559479 Share on other sites More sharing options...
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