Bad ecu?

[Jj231]

An update to a previous post. The first problem I had is with a failed cam ps. I changed the sensor twice and it cures the problem for about a week. Then the good ole p0340 returns and it has the typical issues. (Stalling, hard starting and cutting out)
So the other night, the horn just started blaring on and off for no reason. I ran outside thinking someone broke in. Nope….so I pulled the fuse.
Then today someone at work told me that I left my lights on. The headlight switch was off but the lights were on. Then I noticed that the dash would go from off to standby with the key in my pocket!!!

So when I drove home and pulled in the driveway, I turned the vehicle off and it continued to run for a bit. (Sputtered but still).

So is this a bad ECU? Maybe a bad ground or electrical gremlin? Is the multiple failed cam sensors related?

 

[DadOSix]

An update to a previous post. The first problem I had is with a failed cam ps. I changed the sensor twice and it cures the problem for about a week. Then the good ole p0340 returns and it has the typical issues. (Stalling, hard starting and cutting out)
So the other night, the horn just started blaring on and off for no reason. I ran outside thinking someone broke in. Nope….so I pulled the fuse.
Then today someone at work told me that I left my lights on. The headlight switch was off but the lights were on. Then I noticed that the dash would go from off to standby with the key in my pocket!!!

So when I drove home and pulled in the driveway, I turned the vehicle off and it continued to run for a bit. (Sputtered but still).

So is this a bad ECU? Maybe a bad ground or electrical gremlin? Is the multiple failed cam sensors related?

What year are we looking at? My 06 was doing some crazy stuff (multiple systems crazy) and it turned out to be a weak battery 10ish volts was enough to make the electronics wacky!

 

[john e denson]

My 05 did some strange stuff too when I replaced the alternator. I bought the one recommended from the parts store but it came from Mexico and was not right. when tested it put out too many amps and made my jeep do weird things. Everything went back to normal when I disconnected the battery and installed the correct alternator.

 

[Jj231]

What year are we looking at? My 06 was doing some crazy stuff (multiple systems crazy) and it turned out to be a weak battery 10ish volts was enough to make the electronics wacky!

Mine happens to be an 06

 

[Jj231]

What year are we looking at? My 06 was doing some crazy stuff (multiple systems crazy) and it turned out to be a weak battery 10ish volts was enough to make the electronics wacky!

What year are we looking at? My 06 was doing some crazy stuff (multiple systems crazy) and it turned out to be a weak battery 10ish volts was enough to make the electronics wacky!

Mine is an 06. Did the 10 volts turn the engine over? I have a generic battery in the Jeep but it cranks and cranks until it catches.

 

[Billwill]

Is this a CRD or gasser?

 

[DadOSix]

Mine is an 06. Did the 10 volts turn the engine over? I have a generic battery in the Jeep but it cranks and cranks until it catches.

Strangely enough, it did start and run and charge. The batt had a dead cell 12.6/6 cells = 10.5v

I noticed one weekend when it was super hot outside, that it was a bit slow to crank, and then took right off. Orignally was going to check the starter, then had some electrical oddities that lead me to check the battery voltage.

 

[Jj231]

Is this a CRD or gasser?

Gasser. 3.7

 

[Billwill]

Could be a wiring/earthing problem whereby a wire is earthing to ground or to another random wire....these Jeeps are getting old and wires chafe through to chassis/engine or other wires.....very difficult to find! Engine/chassis grounds get rusty and dirty!

I fixed about 16 wiring issues as above after my 2002 CRD had a collision with a tree....fortunately I know my Electronics and with the correct Wiring Diagrams I could fix them. I still carry my tools/meters and my Laptop with circuit diagrams loaded in my Jeep wherever I go!

I wonder if there is not an issue around your Ignition Switch...either loose/shorting wires or a bad Actuator Pin assembly or the Ignition Switch itself....worth having a look in that area!