dash lites blinking

snowsurfer · Post by **snowsurfer** » Sat Sep 19, 2009 4:02 pm

Got a real weird problem....Yesterday morning started truck up as I do every morning and all the dash warning lights start blinking. Shut it down, restarted it and again all the lights again are blinking. Engine runs fine so I drive it around the block as it continues to blink...get back into my garage shut it down. Start it another time and all is well and back to normal. I drive to work which is mainly freeway and when I get 2 blocks to my office I stop at the red light and the lights go hay wire again!!! Engine runs fine, get to my office parkng stall throw it in park and the dash lights stop flashing but the trans shifter light indicator (PRND321) starts blinking....again engine is fine.
Today the exact thing. I go out during my lunch break and start it up, everythings fine as it was when I went home after work yesterday??????
Any idea's ANYONE??????

roadrunner · Post by **roadrunner** » Sat Sep 19, 2009 4:06 pm

Loose battery cable?

DLP · Post by **DLP** » Sat Sep 19, 2009 6:34 pm

My 01 Crew did the same thing when it had less then 20,000 miles. Turned out to be a bad alternator.

snowsurfer · Post by **snowsurfer** » Sat Sep 19, 2009 8:47 pm

I tried the battery cables first but they were on good....I suspected the alternator as my voltage read just shy of 13v. I've had alternators go bad before but usually the regulator and the headlites will go dim and as you gas it they get brighter but this didn't happen...I also heard a high pitch whinning sound. This afternoon after work it started fine, no lites, no whinning, only happens in the am...What I did notice was at first it showed closer to 14v then after a few minutes down to 13v...

green02crew · Post by **green02crew** » Sun Sep 20, 2009 3:09 am

Alternator not putting out constant voltage when its cold. Mine has been known to do this. Warms up for a bit and starts to run normally. I try to ignore it hoping that someday it won't just die out warming up in my driveway because the alt did have any output. They just don't make things like they used to.

snowsurfer · Post by **snowsurfer** » Sun Sep 20, 2009 10:15 am

Just all of sudden it did this so I was alittle taken aback when all the warning lights started flashing!!!!!
I looked up another post about an alternator mod from ZR2USA AND HENRY J about the alternator sense wire....thought maybe that could be the issue also....

green02crew · Post by **green02crew** » Sun Sep 20, 2009 11:02 am

Wait, warning lights flashing as in on and off or dash lights (gauges ect) dimming, big difference between those two items.

roadrunner · Post by **roadrunner** » Sun Sep 20, 2009 11:59 am

Yes, in his first post he did say dash warning lights. My 01 runs a little above 14v cold and after warm-up settles in at about 13.5v on the dash gauge. Actual voltage is actually about .5-.7 volts higher when checked by external voltmeter at the battery and also with ScanGauge II.
If no loose cables then I am unsure what to send you to look at next other than the normal electrical check ups such as body and engine grounds. Perhaps Brule will have some better ideas. Be sure to keep us advised if you find the problem.

snowsurfer · Post by **snowsurfer** » Sun Sep 20, 2009 1:05 pm

Yes, what alarmed me the was all the warning lites, brake, etc. all were blinking. Truck was cold, overnight first start of the day...When I got to my office 8 miles and idle in the parking lot just the trans ( Park, Reverse, Drive, 3, 2, 1, lites were flickering not the warning lites. Every day so far in the afternoon when leaving work everything is fine??

roadrunner · Post by **roadrunner** » Sun Sep 20, 2009 1:32 pm

I too am chasing a weird ses blinking light problem. Other lights are not blinking. Occasionally ses starts flashing. No codes or history codes either. It then mysteriously quits and may not bother for days/weeks. Frustrating! I hate intermittent seemingly inexplicable electrical problems.

04crewvt · Post by **04crewvt** » Sun Sep 20, 2009 5:33 pm

Blinking SES lights are normally a sign of an problem that has yet to trigger a code. See if it happens under the same weather/driving conditions, a diagnostic scanner that lets you read and record real time information may help if you happen to catch it at the right time.

roadrunner · Post by **roadrunner** » Sun Sep 20, 2009 6:00 pm

Yeah, I've been chasing this thing for 6 months or more. It's so unpredictable it's very difficult to pin down with or without a scanner. Conditions seem to be varied as well. Just plain frustrating!

snowsurfer · Post by **snowsurfer** » Sun Sep 20, 2009 9:06 pm

SES lit, brake lite, all the lites blinking ..no codes set.

Post by **HenryJ** » Mon Sep 21, 2009 6:06 am

roadrunner wrote:Loose battery cable?

Check the cables and connections again, including all the ground straps. Barring that then maybe look to the ignition switch as a suspect?
If it is strictly the instrument cluster, then the connections there perhaps?

kwalsh · Post by **kwalsh** » Tue Sep 22, 2009 9:34 am

I had a similar issue on my 88 S-10. The dash lights, odometer, even the stereo system would flash on & off.
The culprit was a loose ground wire on the parking brake foot pedal, of all places,.... go figure...it took me weeks troubleshooting and I have no idea why the ground wire was landed on the parking brake.

S-10CREWCAB.NET

dash lites blinking

dash lites blinking

blinking lites

alternator