Direct short under dash
#1
Burning Brakes
Thread Starter
Direct short under dash
Before I burn up the car or have a stroke, I have 1 more issue I need help with. I've had the dash in and out several times with courtesy light problems,dash lights, new radio, clock etc and now I have an issue that's even more puzzling. Several times the clock has started and stopped on its own but now the fuse keeps blowing. First the clock would start and after a few minutes, the fuse would blow- At the same time the radio quits working also. Even further the courtesy lights go out(rear ones) as I'm still working on the door ones. Just before I quit today, I put a new fuse in(20) and then connected the battery and got lots of crackling noises at the battery. Strangely the radio has 2 in line fuses to it and they are fine?? Suggestions anyone ? I'm about to put a for sale sign on it !
#2
Le Mans Master
Member Since: Jan 2006
Location: Boca Raton Florida
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Presumably the 2 in line fuses are on different wires: Power and Memory. They should only blow if there is a short in the radio itself or in the wire between the fuse and the radio.
It sounds like you have something cross connected in the dash. Which fuse is blowing? Is the 20 amp fuse what is called for in that position?
If you disconnect the clock all together does the fuse remain ok?
Those old clacks have a motor in there with a momentary contact, sometimes they stick
It sounds like you have something cross connected in the dash. Which fuse is blowing? Is the 20 amp fuse what is called for in that position?
If you disconnect the clock all together does the fuse remain ok?
Those old clacks have a motor in there with a momentary contact, sometimes they stick
#3
Burning Brakes
Thread Starter
short
The fuse is 20 amp, clock=courtesy lights The clock was just rebuilt but I'll disconnect and see what I get- Extremely difficult to work under dash at 6'3 210 and a fat head!! earlier when fuse blew, I had no radio,courtesy lights and radio but all came back on until new fuse blew Have to keep looking
#4
Le Mans Master
Member Since: Jan 2006
Location: Boca Raton Florida
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The fuse is 20 amp, clock=courtesy lights The clock was just rebuilt but I'll disconnect and see what I get- Extremely difficult to work under dash at 6'3 210 and a fat head!! earlier when fuse blew, I had no radio,courtesy lights and radio but all came back on until new fuse blew Have to keep looking
#5
Race Director
The 'crackling sound' you hear at the battery when you connect the cable is NORMAL. It is because you have SOMETHING ON...and requiring power ...thus....being your interior light circuit.
You cigarette lighter and housing can be a culprit.
WHAT YEAR? I can not go by your avatar.
IF you do not have BULBS IN YOUR COURTESY LIGHT SOCKETS in the front....because you wrote: the rear interior light goes out"...the wires can touch and short out the circuit if you do not have a bulb in....OR...take precautions to make sure the WHITE wire does not come out and touch the POWER wire (orange) in the light socket for your floorboards.
Also...possible that the power terminal on the clock is lightly touching the housing and causing the circuit to blow the fuse in time. So the advice of pulling the wire on the clock it a good one....but I would check your front floorboard light first.
DUB
You cigarette lighter and housing can be a culprit.
WHAT YEAR? I can not go by your avatar.
IF you do not have BULBS IN YOUR COURTESY LIGHT SOCKETS in the front....because you wrote: the rear interior light goes out"...the wires can touch and short out the circuit if you do not have a bulb in....OR...take precautions to make sure the WHITE wire does not come out and touch the POWER wire (orange) in the light socket for your floorboards.
Also...possible that the power terminal on the clock is lightly touching the housing and causing the circuit to blow the fuse in time. So the advice of pulling the wire on the clock it a good one....but I would check your front floorboard light first.
DUB
#6
Burning Brakes
Thread Starter
dash
good info Dub Ive messed with the clock too many times and may have not centered it in housing. Will disconnect and see what I have.Also have light in lighter under shift console but it has been working. Car is a 68 this may take awhile. Will eliminate clock power first tks
#7
Burning Brakes
Thread Starter
dash
disconnected the clock put new fuse in and radio and rear courtesy lights work without blowing fuse. The clock was newly refurbished and powers up fine- guess I'll have to make sure connection isnt shorting out. Gonna give it awhile tonight and see if everything is ok by morning. great tips from everyone will check back later on Thanks Paul
#8
Burning Brakes
Thread Starter
short
Believe the clock to be the culprit- disconnected it and hooked battery up after changing fuse- radio works, courtesy lights(ones I have hooked up so far) went through all the motions with lights,exterior and interior and had to replace inner rear brake light bulb and everything works EXCEPT-LOL rear left signals work both with lights on and off as designed but blue wired bulb in dash for left signal illuminates with the lights both parking and headlight??? before I changed bulb the left rear signal would not flash- ok now but wonder why dash sihanl lights when lights are pulled on.. Happy to have gotten this far looked at clock connector and end was in contact metal to metal with dash will fix and try again Light puzzles me though - ready to drive have only put7 miles on since january 427 4 speed
#9
Race Director
Believe the clock to be the culprit- disconnected it and hooked battery up after changing fuse- radio works, courtesy lights(ones I have hooked up so far) went through all the motions with lights,exterior and interior and had to replace inner rear brake light bulb and everything works EXCEPT-LOL rear left signals work both with lights on and off as designed but blue wired bulb in dash for left signal illuminates with the lights both parking and headlight??? before I changed bulb the left rear signal would not flash- ok now but wonder why dash sihanl lights when lights are pulled on.. Happy to have gotten this far looked at clock connector and end was in contact metal to metal with dash will fix and try again Light puzzles me though - ready to drive have only put7 miles on since january 427 4 speed
YOUR problem is telling me that when you have your PARK LIGHTS ON...the current is jumping to the turn signal circuit...which is why your light in your dash is lightly up.
DUB
#10
Burning Brakes
Thread Starter
light
Dub, The bulb is a double filament bulb 1157 I believe. It only will fit on one way in the socket- It worked fine originally before I started messing with dash. My guess is it might be the bulb socket for blue wired light in dash. I looked at it this morning and the metal insert in socket doesnt seat very well. Going to try another pigtail and see what happens- dont think its grounding properly Does that make any sense?
#11
Race Director
Look at the front park/signal lights.
DUB
DUB
#13
Le Mans Master
My 72 LT-1 had an intermittent high speed misfire for months.....finally fried the fuseable link off the horn relay to fuse box. I went through wiring.....replaced harness to starter solenoid and drove it on a 100+ mile trip.....no problems. Left Vette at my buddies house.....let him drive it.....it quit on him.....fuseable link opened up again! Being a genius....I put a little bigger link in that time.....about ready to drive off on a Sunday morning to an Autocross 45 miles away and while LT-1 is warming up in the driveway.....starts missing....then SMOKE! out of dash! The harness had worn through by the cast iron steering column brace after 96K miles! Electrical problems can be hard to track down at times!
#14
Burning Brakes
Thread Starter
smoke
Wow, thankfully my issues are minor.The light pigtail to the blue signal light wire doesnt completely fit snug into dash- it came apart on me and I did best I could to put metal retainer back in- I'm going to replace with a new pigtail and see where I am. signal works fine with parking and headlights off. when they are on- l signal in dash illuminates- has to be a ground- I think Thanks
#15
Race Director
It is NOT the ground of your speedo/tach housings. AND it is more than likely NOT the socket. IF the turn signal light in the dash is lighting up and blinking WHEN THE HEADLIGHTS ARE OFF and the turn signals indicators are BRIGHT...then that is NOT the problem.
When the turn signal indicator LIGHT IN your speedo/tach housings lights up...are BOTH turn signal indicators in your dash lighting up or only ONE lighting up WHEN you turn on the headlights???
Did you look at the front park/signal lights, sockets and wiring harness connectors. Being a 68...you can loose a ground and cause for a problem...and it will be the one that is showing up in the dash when the headlight switch is pulled. IF it is BOTH indicators...I would run a ground wire to each and check it . ALSO can be a bulb in these sockets not in correctly.
make sure all bulbs are good and seated and clean terminals.
DUB
When the turn signal indicator LIGHT IN your speedo/tach housings lights up...are BOTH turn signal indicators in your dash lighting up or only ONE lighting up WHEN you turn on the headlights???
Did you look at the front park/signal lights, sockets and wiring harness connectors. Being a 68...you can loose a ground and cause for a problem...and it will be the one that is showing up in the dash when the headlight switch is pulled. IF it is BOTH indicators...I would run a ground wire to each and check it . ALSO can be a bulb in these sockets not in correctly.
make sure all bulbs are good and seated and clean terminals.
DUB
#16
Burning Brakes
Thread Starter
lighting
Dub, when lights are off the signals work perfectly fine. Only when the parking or headlights are on does the left signal only come on. If I read you correctly, I need to check both front and rear lights for poor connection or bulbs in the wrong way. The side markers,tail and stop lights work fine along with the front signals. I had a poor ground in left inside tail light but fixed it but still the light comes on. I'll check all the left side sockets and bulbs and see what I find.. You'd think with all the difficult electrical issues that are now fixed that this would be simple!!! Thanks
#17
Race Director
Dub, when lights are off the signals work perfectly fine. Only when the parking or headlights are on does the left signal only come on. If I read you correctly, I need to check both front and rear lights for poor connection or bulbs in the wrong way. The side markers,tail and stop lights work fine along with the front signals. I had a poor ground in left inside tail light but fixed it but still the light comes on. I'll check all the left side sockets and bulbs and see what I find.. You'd think with all the difficult electrical issues that are now fixed that this would be simple!!! Thanks
BECAUSE the right side is NOT doing it. You have 'something' going on in the left circuit...OBVIOUSLY.
I SWEAR you are having 12 volts jumping to the blue wire in the front somewhere. It is NOT possible that it is in the rear wiring due to if you look at your wiring diagram...the light blue wire is the same that goes to your speedometer turn signal indicator as it goes to your left park/signal light in the front.
CAREFULLY inspect the front PARK/SIGNAL light socket....along with the 3 wires that join in the connector at the end of the pigtail wiring harness.
AND...YOU are ABSOLUTELY positive that the brightness of your turn signals is BRIGHT and not actually blinking on the PARK light element in the bulb????
DUB
#18
Burning Brakes
Thread Starter
lights
Dub spent a few minutes tonight checking the lights. The signals work brightly with headlights off. With lights on and key off the left signal on dash does light. When the key is on and signal lights are used the left does blink front and rear but does not blink in the dash( just stays on solid.) I'll check in to the front left sockets,and pigtail tomorrow. By any chance can the dash bulbs be put in wrong? When I took dash outand removed bulbs several of the sockets came apart and I had to put back together. I have a new pigtail I was going to splice in and change bulb at same time- waste of time? this car drives me nuts!! Today I get a pic of 69 Chevelle ss L78 triple black car I sold last year and guy won a trophy last weekend as big as he is in Indiana!!! I sold a 3 time Super Chevy 63 vette roadster and had a National award winning 66 Cyclone GT- Why I sell them I'll never know
#19
Race Director
Dub spent a few minutes tonight checking the lights. The signals work brightly with headlights off. With lights on and key off the left signal on dash does light. When the key is on and signal lights are used the left does blink front and rear but does not blink in the dash( just stays on solid.) I'll check in to the front left sockets,and pigtail tomorrow. By any chance can the dash bulbs be put in wrong? When I took dash outand removed bulbs several of the sockets came apart and I had to put back together. I have a new pigtail I was going to splice in and change bulb at same time- waste of time? this car drives me nuts!! Today I get a pic of 69 Chevelle ss L78 triple black car I sold last year and guy won a trophy last weekend as big as he is in Indiana!!! I sold a 3 time Super Chevy 63 vette roadster and had a National award winning 66 Cyclone GT- Why I sell them I'll never know
IF your turn signals work.....and that ALL of the lights that are supposed to blink....blink...including your front side marker lights when that side is having the turn signals on.
Then turn on your headlights WITHOUT the turn signals being on and make sure they all work. IF they are all working...then the system should be fine.
I would be suspect of the brown wire that is your park light circuit and the left turn signal circuit are coming in contact somewhere.
DUB
#20
Burning Brakes
Thread Starter
light
Thanks DUB I'll check as you mentioned. Aggravating but all these worked fine before I pulled dash off to put new gauges in and get dash lights working along with a new radio. I believe all lights work fine with just switch and no signals on. Thanks for the help and I'll keep reporting back as I get further if you dont mind Paul