I hate electrial problems [Archive] - xjtalk

OrangeXJ

12-17-2011, 05:11 PM

Driving around yesterday the "check Gauges" light came on. Voltage gauge was showing 19 volts. A short time later it was back to normal. Drove it today and it did it again I had a volt meter with me and the voltage at the battery was 12.95. While I was checking the voltage it started to run ruff. Looked at the dash and the check engine light was on then it died. No power any where. It probably blew the main fuse. It just got a new engine in it and maybe a wire got pinched. But I don't know why the voltage gauge is showing high.

Any thoughts ? :bang:

BlueXJ

12-21-2011, 09:16 PM

I have a friend who keeps blowing the 30 amp fuse and that feeds the ECU, so I speculate you have a computer short.

OrangeXJ

12-22-2011, 03:07 AM

no bad fuse must be ECU

Carves

12-22-2011, 04:33 AM

Got a battery temp sensor in that XJ ??

Not sure on the how the highs and lows work on it to determine its faulty ... but if its sending cold temp messages then the PCM ups the voltage rate.

Maybe swap the TJ one in for a comparison ??

OrangeXJ

12-22-2011, 06:26 AM

The problem is on the TJ can't do any swaping it's a 97 and they are a strange beast. I can only use 97 parts on it

seu83

12-22-2011, 07:18 AM

My friend had a 99' xj doing crazy stuff like this. Turned out to be his altenator.

xj98

12-22-2011, 08:12 AM

My friend had a 99' xj doing crazy stuff like this. Turned out to be his altenator.

^x2 I'd probably start at the alternator. Did the lights get really bright then the gauge went up? If the voltage did go up that high it could have damaged the pcm.

jeepxj95

12-23-2011, 01:15 AM

that or the voltage regulator which is in the ecu

cantab27

12-23-2011, 01:26 AM

well there's the problem ,,its a tj

OrangeXJ

12-23-2011, 03:28 AM

well there's the problem ,,its a tj

It's green

cantab27

12-23-2011, 03:30 AM

well everyone knows hardcore tj are blue...............

OrangeXJ

12-23-2011, 03:30 AM

^x2 I'd probably start at the alternator. Did the lights get really bright then the gauge went up? If the voltage did go up that high it could have damaged the pcm.

When the gauge on the dash was saying 19 volts I put a meter on the battery and it said 12.5 volts.

xj98

12-23-2011, 02:31 PM

When the gauge on the dash was saying 19 volts I put a meter on the battery and it said 12.5 volts.
I guessing it wasnt running when you did this if you had 12.5v. if thats the case then im guessing the computer since it died on you too. any codes?

OrangeXJ

12-24-2011, 07:49 AM

It was running and I don't have a code reader

xj98

12-24-2011, 01:41 PM

It was running and I don't have a code reader

Well if it was running you should be reading somewhere in the 14v to 14.6v range. if your reading 12.9v while the engine is running your alternator isn't charging or charging very little.

OrangeXJ

12-30-2011, 08:52 AM

I removed the ECU and everything started working so I suspect it is bad. I sent it off to get inspected/repaired. Before I install it I will check the alt.

cantab27

12-30-2011, 11:38 AM

have you wheeled it yet...how did it go if you have

uberxj92

01-03-2012, 09:54 PM

The problem is on the TJ can't do any swaping it's a 97 and they are a strange beast. I can only use 97 parts on it

my best friend has a 99 & like you said dang thing is a pain to work on cause you have to use year , color, & moon phase specific parts LOL.

LizardRunner

01-04-2012, 08:10 PM

yep sounds like a bad ECU, if you get it back in I bet the voltage problem goes away. I had a similar problem but the computer checked out ok, replaced the alternator (twice) and no problems 6 months down the road. I got lucky I was told.

OrangeXJ

01-07-2012, 06:04 AM

Got the ECU back yestreday hooked it up now everything is working properly.Drove it to work today (42 miles) no problems.

4.3LXJ

01-07-2012, 10:09 AM

Good to hear it works now.

cantab27

01-07-2012, 10:48 AM

Got the ECU back yestreday hooked it up now everything is working properly.Drove it to work today (42 miles) no problems.

good news about it going again greg,,, bad news about going to work but....what did they do to ECU , replace or repair,,can they repair them ???

uberxj92

01-07-2012, 09:19 PM

they can "reman" the ecu's. or if you have a '91-'95 xj the ecu's are pretty much universal & boneyards have them. depending on which "96" xj you have the ecu may be specific.
cheapest my bud with the 99 xj found for his when he had to replace it was $350 out of south florida

xj98

01-08-2012, 07:49 AM

Got the ECU back yestreday hooked it up now everything is working properly.Drove it to work today (42 miles) no problems.
Good to hear you fixed it! Electrical problems can be a real pain! I was hunting 80miles away from home in my old 87 cherokee when it died on me. It was running perfectly fine, stop for gas, and wouldn't start back up. Turned out to be the the pcm or fuel injection modural. Whatever it had, it just decided to stop working. Had to get it towed home.

uberxj92

01-08-2012, 01:30 PM

OH FREAKIN GREAT!!!!!!!!!! LOL just today the 92 "sadness" stalled on the beach...cranked & cranked finally caught. sounded like some POS ford v8 until the comp made some adjustments & then ran fast. LOL LOL i knew it lol talking about electrical & LOL ...pulling the dist & coil ( they are way old), gonna tune it up ( been 1 month on that), gonna flush the fuel system. got a spare ecu too. lol lol . o yea just installed a brand new ignition ( electrical ) switch. lol

Mudderoy

01-08-2012, 02:01 PM

Got the ECU back yestreday hooked it up now everything is working properly.Drove it to work today (42 miles) no problems.

What company was that Greg? I was thinking about getting another for my 1998 XJ and have them go through it.