shilohwestphal Posted January 25, 2023 Share Posted January 25, 2023 Had a very similar problem with a 04 cv713 Granite 427 this week. Just loaded and was headed to the scale when the truck just died. The truck would not start, it would turn over just fine but would not fire. Noticed none of the gauges were working when I tried to start the truck. The truck also had a "no data" or "no info" displayed on the odometer. I called my local Mack dealer and talked to the main tech service man. He said the ecm is probable bad. Wasnt good news. but anyway So I started checking everything I thought might be the culprit, fuses, plugs, grounds, relays, and so forth. What I found and what got the truck running was I found moisture in the ecm connection plugs. Dried it out and plugged it back up, two plugs, and truck fired right up. All the gauges were working too. Have not yet, but Friday will put some dielectrical grease on both plugs. Hopefully we will not have this issue again. Quote Link to comment Share on other sites More sharing options...
Mackpro Posted January 25, 2023 Share Posted January 25, 2023 25 minutes ago, shilohwestphal said: Had a very similar problem with a 04 cv713 Granite 427 this week. Just loaded and was headed to the scale when the truck just died. The truck would not start, it would turn over just fine but would not fire. Noticed none of the gauges were working when I tried to start the truck. The truck also had a "no data" or "no info" displayed on the odometer. I called my local Mack dealer and talked to the main tech service man. He said the ecm is probable bad. Wasnt good news. but anyway So I started checking everything I thought might be the culprit, fuses, plugs, grounds, relays, and so forth. What I found and what got the truck running was I found moisture in the ecm connection plugs. Dried it out and plugged it back up, two plugs, and truck fired right up. All the gauges were working too. Have not yet, but Friday will put some dielectrical grease on both plugs. Hopefully we will not have this issue again. Good find on that., Mack had a issue with the coolant level sensor leaking coolant into the wiring between the copper and insulation. The coolant would travel back into the engine ECM . One of the side effects was the dash cluster going out. Mack Service Bulletin SB237009 covers the issue. They came out with a jumper wire to go between the coolant level sensor and engine harness to block the coolant from getting to the ECm . Unplug your coolant level sensor abs see if it’s wet inside. Quote Link to comment Share on other sites More sharing options...
shilohwestphal Posted January 26, 2023 Share Posted January 26, 2023 Good info. I will check this today. The truck had a slow coolant leak for the past couple years. This past summer we were adding roughly half gallon a day. The truck originally had the two plastic purge/overflow tanks. The radiator cap was not sealing so this was a suspect coolant leak. Both of these plastic tanks were replaced this past summer with the new aluminum single purge tank. And then in December the radiator was replaced. I suspect the motor was cleaned / sprayed off during this last repair. Quote Link to comment Share on other sites More sharing options...
shilohwestphal Posted January 26, 2023 Share Posted January 26, 2023 if this truck doesnt already have this jumper wire harness already installed, I will order one. thanks Quote Link to comment Share on other sites More sharing options...
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