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turn signal problem
- Thread starter GT350
- Start date
AzPete
Well-Known Member
Brake lights work?
Sounds like a basic turn signal switch issue and needs replaced. Yours are all located in the column so it should be one switch......I think.
Sounds like a basic turn signal switch issue and needs replaced. Yours are all located in the column so it should be one switch......I think.
AzPete
Well-Known Member
Reviewed the attached schematic a bit and I still feel it leads to the turn signal switch as all systems go thru it...brakes, emergency, and turn lights.
http://hammar.dyndns.org/~djhamma/wiring/1968/E7.jpg
http://hammar.dyndns.org/~djhamma/wiring/1968/E7.jpg
That's fairly common. I put black electrical tape on the back-side of the switch, because sometimes the rivets hit the steering column base, which is ground.
I appreciate return business, but what is up with 69's all of a sudden? I had 2 last week, 4 in the queue, and this now makes five? 1969's are the most popular year for underdash refurbishment, but this string of 7 is most unusual!
AzPete
Well-Known Member
All the good 66 cars are done....now moving the the 2nd in line..... :hide
I'd start by disconnecting the plug to the rear tail-lights, and try again. If the circuit still blows, then remove the bulbs up front. If the circuit still blows, then you have a wiring issue. This process will allow you to isolate whether the problem is up front or in the back.
Somewhere, you have a dead short. I've found reproduction tail-light buckets are notorious for shorts, as the bulb contact leads will sometimes contact one another and that causes all sorts of issues.
For 1968, there's only one other system on the circuit, and that's the cigarette lighter. I'd check that out carefully as well. These systems are fused to battery power, so it shouldn't make a difference if the engine is running or not. Does the fuse blow when you go to ACC, or to RUN, or only after CRANK? My suspicion is that there's something tied to the cigarette lighter line...
Somewhere, you have a dead short. I've found reproduction tail-light buckets are notorious for shorts, as the bulb contact leads will sometimes contact one another and that causes all sorts of issues.
For 1968, there's only one other system on the circuit, and that's the cigarette lighter. I'd check that out carefully as well. These systems are fused to battery power, so it shouldn't make a difference if the engine is running or not. Does the fuse blow when you go to ACC, or to RUN, or only after CRANK? My suspicion is that there's something tied to the cigarette lighter line...
I think you've found your problem circuitry. Remove the tach from the circuit and try again!
Disconnect both the flasher and the emergency flasher cans, along with the cigarette lighter connector. This will isolate any connections to that particular fused line, unless someone previously has tapped into it.
The crank signal is a separate line that goes to the NSS and then to the starter solenoid. On a 68 non-tach dash, there are two other lines that are hot when the key is in RUN or CRANK: 904, which runs from the ignition switch to a 4 pin plug on the left side of the harness, and from there to the coil and starter solenoid via the gauge and headlight harness, respectively, and a dash wire (red/yellow) that powers up the brake indicator lamp. Somewhere in this circuitry is a dead short. I'd start by disconnecting the dash connectors first. If that doesn't do it, find the 4 prong plug (the black one) and disconnect it. By doing so, you'll also disconnect the NSS line. Turn the key to RUN and try that (you won't be able to crank the starter, though).
The crank signal is a separate line that goes to the NSS and then to the starter solenoid. On a 68 non-tach dash, there are two other lines that are hot when the key is in RUN or CRANK: 904, which runs from the ignition switch to a 4 pin plug on the left side of the harness, and from there to the coil and starter solenoid via the gauge and headlight harness, respectively, and a dash wire (red/yellow) that powers up the brake indicator lamp. Somewhere in this circuitry is a dead short. I'd start by disconnecting the dash connectors first. If that doesn't do it, find the 4 prong plug (the black one) and disconnect it. By doing so, you'll also disconnect the NSS line. Turn the key to RUN and try that (you won't be able to crank the starter, though).
Look for the fuse blowing or not. I'm trying to isolate what part of the circuitry is blowing the fuse. Your car has a Neutral Safety Switch wires; it is jumpered if you have a manual tranny, or goes to the automatic transmission and back again. The plug is on the engine side of the firewall near the oil/temp/coil harness, and is a four pin plug.
And just to be clear: is it the lower left horizontal fuse that is always blowing?
And just to be clear: is it the lower left horizontal fuse that is always blowing?
car has a manual trans the fuse thats blowing is on the lower rh side when your looking underdash from drivers side 20 amp, can a bad bulb on the turn signal side cause this even if my hazards work ? i will check the nss wires today,as for turn signals it seems im not getting any output from switch to turn signals even though the same wire has voltage for hazards and there is 14v on each terminal on flasher side"Midlife" said:
Ahh....that's a different set of wiring than what I was thinking, The fuse that keeps blowing is the courtesy lights and doorjamb lines, but it is still independent of the car in the RUN or CRANK condition.
OK, let's re-set and go back to the beginning. You have two problems: one related to the turn signals and the other related to blowing fuses.
Turn Signals: you've replaced the turn signal switch, and both left and right signals don't work. Have you replaced the flasher can for normal operation? Have you replaced bulbs with LED's by any chance?
Fuse Blowing: What do you see on the car that indicates the fuse is blowing? When you say the fuse blows when you start the car, do you mean when you turn the key to RUN, to ACC, or to CRANK? Have you tapped into any of the green/yellow or black/blue wires under the dash? For some 68 models, these lines also go to the trunk on the driver's side.
OK, let's re-set and go back to the beginning. You have two problems: one related to the turn signals and the other related to blowing fuses.
Turn Signals: you've replaced the turn signal switch, and both left and right signals don't work. Have you replaced the flasher can for normal operation? Have you replaced bulbs with LED's by any chance?
Fuse Blowing: What do you see on the car that indicates the fuse is blowing? When you say the fuse blows when you start the car, do you mean when you turn the key to RUN, to ACC, or to CRANK? Have you tapped into any of the green/yellow or black/blue wires under the dash? For some 68 models, these lines also go to the trunk on the driver's side.