Truck reboots at 72mph towing 8K with ETC fault

[JJC72]

10/2020 Ram 2500, 6K miles. Towing 8K down hiway, cruise set to 72mph, smooth road, tow/haul mode engaged, exhaust brake set to auto. All of sudden it was like the ignition switch was turned off and back on real quick. Cruise control dropped off, tow/haul mode and exhaust brake modes dropped off, alternator stopped charging (voltage went to 12.5 then started climbing again to 13.8), throttle was momentarily unresponsive. Then all back to normal with an flashing ETC (red lightning bolt) on. Upon shutdown and restart, ETC was on solid (red lightning bolt). Dealer said updated ECM software, and cleared code. Now happened again, same exact circumstance. Any others have this??

 

[Brewbud]

10/2020 Ram 2500, 6K miles. Towing 8K down hiway, cruise set to 72mph, smooth road, tow/haul mode engaged, exhaust brake set to auto. All of sudden it was like the ignition switch was turned off and back on real quick. Cruise control dropped off, tow/haul mode and exhaust brake modes dropped off, alternator stopped charging (voltage went to 12.5 then started climbing again to 13.8), throttle was momentarily unresponsive. Then all back to normal with an flashing ETC (red lightning bolt) on. Upon shutdown and restart, ETC was on solid (red lightning bolt). Dealer said updated ECM software, and cleared code. Now happened again, same exact circumstance. Any others have this??

Yikes. Not something I would want to happen. Not sure what would cause that but I would be looking for a bad ground connection. I would also check all the fuses in the fuse box. Those are known to be loose from the factory on some trucks.

 

[JJC72]

Yikes. Not something I would want to happen. Not sure what would cause that but I would be looking for a bad ground connection. I would also check all the fuses in the fuse box. Those are known to be loose from the factory on some trucks.

Dealer stated codes were for loss of ECM power/communicatuon. So that makes sense. Now just to find out why?

 

[JJC72]

dealer stated they found an internal short inside alternator causing ECM power to short intermittently. New alternator on order, 3 days or so. Lets keep our fingers crossed.

 

[Squatch]

dealer stated they found an internal short inside alternator causing ECM power to short intermittently. New alternator on order, 3 days or so. Lets keep our fingers crossed.

This is why I miss trucks without brains.

 

[Bozo]

This is why I miss trucks without brains.

Me too, but unfortunately, today’s politicians have filled that void........many of the general population, as well.

 

[Squatch]

Me too, but unfortunately, today’s politicians have filled that void........many of the general population, as well.

Brain donors

 

[JJC72]

Alternator replaced, so far so good. Had great tech at dealership, very descriptive and thorough in his troubleshooting diagnostic data. Best i have seen in a long time at a dealer.

 

[gimmie11s]

Alternator replaced, so far so good. Had great tech at dealership, very descriptive and thorough in his troubleshooting diagnostic data. Best i have seen in a long time at a dealer.

Hang on to his phone number and ask if he has any friends at other dealerships throughout the country haha.

That's a rare breed right there.

 

[JJC72]

problem is back, so not as good as I preached for them. Now replacing the ECM with a 5/6 week lead time!! And still this will be a shotgun troubleshooting event!! UGH!!