5.0 GXI C no start

[fisherman73]

Cranks no start. Intermittently blows 15 amp ignition fuse. Occasionally will try and start but almost always has no spark. Replaced, ignition module, coil, and crank sensor, no change. Crank sensor does read on tach when cranking. No codes. A wiring diagram might help. Suspect ECM failure.

 

[alldodge]

This is for V6 but yours will be the same

 

[alldodge]

Spark test

 

[fisherman73]

Thank you! Specifically what I am looking for specifically is what F3 fuse (15amp) ignition feeds. It seems that it powers the ECM as well as the ignition circuits but that’s a guess. It will intermittently blow when key is turned on or even while running. All of the diagrams I have found show F3 as a 20 amp fuel pump fuse.

 

[ripjmk]

I believe if you look in the cap of the fuse / relay box it will state that F3 is the ignition fuse. The number on the wiring diagrams is relating to the diagram legend not the fuse number. The fuse is a 15 A and feeds the ignition control module, all the injectors and the ECM. The relay is energized any time the ignition key is on. I would check for a ground with a DVM and the ECM J2 connector disconnected on pin 19 of J2 wiggling all the wires you can. I would look long and hard at all the other connected components before replacing the ECM.

 

[fisherman73]

I believe if you look in the cap of the fuse / relay box it will state that F3 is the ignition fuse. The number on the wiring diagrams is relating to the diagram legend not the fuse number. The fuse is a 15 A and feeds the ignition control module, all the injectors and the ECM. The relay is energized any time the ignition key is on. I would check for a ground with a DVM and the ECM J2 connector disconnected on pin 19 of J2 wiggling all the wires you can. I would look long and hard at all the other connected components before replacing the ECM.

Thanks! Exactly my thoughts! Super expensive!

 

[fisherman73]

Also might add intermittently no double beep when key is turned on.

 

[alldodge]

The distributor you have is a HSV and uses what most call a crap cap.

They go out without warning and cause all kinds of problems. It's best to keep a spare on board. Would suggest replacing it and if it doesn't help at least it's been ruled out and keep as spare

 

[QBhoy]

Check a look at the ignition wiring and terminal at the engjne. Make sure it’s not come adrift and shorting onto the block or similar. Check the diz cap doesn’t have moisture in it and causing issues too.

 

[fisherman73]

Update on this still ongoing issue. Pulled the ECM out and sent it to rebuilder. No problem found but also no surprise because it was running perfectly when I pulled it. Cleared multiple codes, all likely set when I was testing, unplugging things etc when the no start issue occurred. After reinstalling it barely started, at times wouldn’t start at all then would magically run. One consistent issue I now am having though is audible alarm is completely random, sometimes double beep with ignition on, sometimes no double beep, sometimes beep continues while running even though it’s a cold engine with 50psi oil pressure. What controls the audible alarm? ECM? I see no other control unit but can’t seem to find anything on the internet about it.

 

[QBhoy]

Update on this still ongoing issue. Pulled the ECM out and sent it to rebuilder. No problem found but also no surprise because it was running perfectly when I pulled it. Cleared multiple codes, all likely set when I was testing, unplugging things etc when the no start issue occurred. After reinstalling it barely started, at times wouldn’t start at all then would magically run. One consistent issue I now am having though is audible alarm is completely random, sometimes double beep with ignition on, sometimes no double beep, sometimes beep continues while running even though it’s a cold engine with 50psi oil pressure. What controls the audible alarm? ECM? I see no other control unit but can’t seem to find anything on the internet about it.

See if you can get the manual. It’s all listed in there. Loads of things on a gxi can trigger an alarm. Every single sensor there is can do this. Check the faults shown again. If there is nothing…it could symbolise a fault to the main power circuit. Look towards the main circuit breaker on the engine then. And it’s wiring associated. Check ignition circuitry, main earths etc etc.

 

[alldodge]

The ECM controls the alarm

Was blowing a fuse then won't start at times, and not repeatable
There is a bad connection or chaffed wire somewhere in the harness is my guess