electrical nightmare

mudseeker · 11-17-2007, 11:07 PM

some of you may remember me mentioning my check gauge light problem. it seems to have gotten worse. it used to only happen at start up when cold out side. now it has showen up after many minutes on the road during normal operating temp. i thought it was a faulty temp sensor but todays events have me confused.
the light doe not flash or stay solid. it just flickers from 1 second up to 30 seconds.
it took about an hour but i got a vidio from my phone to the computer and finally to photobucket. enjoy.

mudseeker · 11-18-2007, 04:13 PM

no one

mrjohnwayne · 11-18-2007, 05:27 PM

man I couldn't even begin where to think about looking. that is wierd...

Hayden · 11-19-2007, 03:07 PM

Did it start doing it after you added or modified anything. If so that'd be a good place to start. Hate to see something go wrong with winter coming upon us.

mudseeker · 11-19-2007, 03:21 PM

been doing it ever since i overheated it twice during the winter.

that's why i thought it was the temp sensor. it used to only do it at start up during cold wet mornings, now it's totally random and is getting worse.
my electrical instructor suggested a cracked circuit board.

crabtruck · 11-19-2007, 05:31 PM

You are getting some type of ground fault (not a hot short) between lamp and PCM.
Pull dash and inspect the trace from lamp to edge connector for possible bridge
from solder, debris, or even a bug (some can cunduct pretty good).
Also check wires from connector to PCM for abration damage.
Failing either of those, it's being generated through the PCM
and should show up through OBD-II info, likely in real time.

mudseeker · 11-20-2007, 11:34 AM

i have run data stream info many times with the tech II at the shop and nothing seems to be out of spec.
but i can never get the light to come on when i am testing it. lol
once i find a wiring diagram i plan to pull the cluster out.

crabtruck · 11-20-2007, 01:47 PM

Don't need a wiring diagram to follow the trace, you would have to anyways.

mudseeker · 11-29-2007, 08:42 PM

$150 later and the problem is fixed.

story first then i'll tell you guys the fix, or maybe i'll let you guess.
i was on my way to class on wed when the check gauge came on again,
this time the speedo started jumping along with the tach.
the gear indicator light would also dim at the same time.
once i got to town the speedo went from 35 to 65 twice then died
along with the tach and gear indicator. i wasn't too concerned at that point,
until i tried to climb up the school driveway,
no power at all. i pulled into a bay and pulled the codes,
had a few TCC codes and a 1-2 code and 3-2 code
p1860, p0740, p0753, p0758, p0785 for those who are curious.
lets see what you can come up with,. with the info i gave you

crabtruck · 11-29-2007, 09:06 PM

Based on the new symptoms being attributed to the old check lite thing, I'm going to guess VSS buffer problem. Was maybe gonna go with pcm but not likely. Too drugged out on cold meds to look up those codes. Secondary guess might be shorting TCC switch but that would not have played this way, other probmlesd. Ferschizle?

11-17-2007, 11:07 PM	#1
mudseeker Senior Moderator Join Date: Feb 2006 Location: michigan Posts: 6,374	electrical nightmare some of you may remember me mentioning my check gauge light problem. it seems to have gotten worse. it used to only happen at start up when cold out side. now it has showen up after many minutes on the road during normal operating temp. i thought it was a faulty temp sensor but todays events have me confused. the light doe not flash or stay solid. it just flickers from 1 second up to 30 seconds. it took about an hour but i got a vidio from my phone to the computer and finally to photobucket. enjoy. __________________ i'd rather be hunting

11-18-2007, 04:13 PM	#2
mudseeker Senior Moderator Join Date: Feb 2006 Location: michigan Posts: 6,374	no one __________________ i'd rather be hunting

11-18-2007, 05:27 PM	#3
mrjohnwayne Senior Moderator Join Date: Apr 2005 Location: Texas Posts: 3,722	man I couldn't even begin where to think about looking. that is wierd... __________________ John Wayne 2000 F-350 7.3L Powerstroke 4x4

11-19-2007, 03:07 PM	#4
Hayden Senior Member Join Date: May 2006 Location: Bay City,Michigan Posts: 382	Did it start doing it after you added or modified anything. If so that'd be a good place to start. Hate to see something go wrong with winter coming upon us. __________________ There Is No Replacement For Displacement

11-19-2007, 03:21 PM	#5
mudseeker Senior Moderator Join Date: Feb 2006 Location: michigan Posts: 6,374	been doing it ever since i overheated it twice during the winter. that's why i thought it was the temp sensor. it used to only do it at start up during cold wet mornings, now it's totally random and is getting worse. my electrical instructor suggested a cracked circuit board. __________________ i'd rather be hunting

11-19-2007, 05:31 PM	#6
crabtruck Senior Member Join Date: Jul 2007 Location: on your 9 Posts: 3,364	You are getting some type of ground fault (not a hot short) between lamp and PCM. Pull dash and inspect the trace from lamp to edge connector for possible bridge from solder, debris, or even a bug (some can cunduct pretty good). Also check wires from connector to PCM for abration damage. Failing either of those, it's being generated through the PCM and should show up through OBD-II info, likely in real time.

11-20-2007, 11:34 AM	#7
mudseeker Senior Moderator Join Date: Feb 2006 Location: michigan Posts: 6,374	i have run data stream info many times with the tech II at the shop and nothing seems to be out of spec. but i can never get the light to come on when i am testing it. lol once i find a wiring diagram i plan to pull the cluster out. __________________ i'd rather be hunting

11-20-2007, 01:47 PM	#8
crabtruck Senior Member Join Date: Jul 2007 Location: on your 9 Posts: 3,364	Don't need a wiring diagram to follow the trace, you would have to anyways.

11-29-2007, 08:42 PM	#9
mudseeker Senior Moderator Join Date: Feb 2006 Location: michigan Posts: 6,374	$150 later and the problem is fixed. story first then i'll tell you guys the fix, or maybe i'll let you guess. i was on my way to class on wed when the check gauge came on again, this time the speedo started jumping along with the tach. the gear indicator light would also dim at the same time. once i got to town the speedo went from 35 to 65 twice then died along with the tach and gear indicator. i wasn't too concerned at that point, until i tried to climb up the school driveway, no power at all. i pulled into a bay and pulled the codes, had a few TCC codes and a 1-2 code and 3-2 code p1860, p0740, p0753, p0758, p0785 for those who are curious. lets see what you can come up with,. with the info i gave you __________________ i'd rather be hunting

11-29-2007, 09:06 PM	#10
crabtruck Senior Member Join Date: Jul 2007 Location: on your 9 Posts: 3,364	Based on the new symptoms being attributed to the old check lite thing, I'm going to guess VSS buffer problem. Was maybe gonna go with pcm but not likely. Too drugged out on cold meds to look up those codes. Secondary guess might be shorting TCC switch but that would not have played this way, other probmlesd. Ferschizle?

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