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Old 03-18-2017, 04:22 PM   #26
randy500
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Re: Signal lamps help again

Here is the wiring diagram, simplified to remove the turn signal contacts.
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Old 03-18-2017, 04:25 PM   #27
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Re: Signal lamps help again

That light glows because the front turn signal bulb is shorted internally or the housing is shorted causing "some" voltage from the brown wire to the indicator Dk blue wire
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Old 03-18-2017, 04:26 PM   #28
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Re: Signal lamps help again

The brown wire is the running lights and can only get to the dk blue wire through the left front turn signal lamp or housing.
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Old 03-18-2017, 04:27 PM   #29
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Re: Signal lamps help again

Do you have a test light?
Can you make one by soldering a wire to the side of a light bulb?
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Old 03-18-2017, 04:49 PM   #30
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Re: Signal lamps help again

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Stop, turn and brake is he same yellow and green wires at the rear. Difference is source of poser through turn signal switche, do you have 4 way flash at rear?
Flashers work the front and left rear. Not rt rear.
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Old 03-18-2017, 04:53 PM   #31
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Re: Signal lamps help again

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That light glows because the front turn signal bulb is shorted internally or the housing is shorted causing "some" voltage from the brown wire to the indicator Dk blue wire
I'll trace these wires may be the source of the problem. I must of hit some wire pulling the column out. Thanks for the diagram. Done for the day get back on it tomorrow.
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Old 03-18-2017, 05:02 PM   #32
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Re: Signal lamps help again

I think since you worked on the column the dark green wire on the wiring harness side of the turn signal switch does not have contact through the connection.
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Old 03-19-2017, 03:41 PM   #33
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Re: Signal lamps help again

Ok figured out I have a short at the left front signal lamp. Got rid of the glowing signal indicator in the dash. Now the rear I just have a left blinking signal lamp and left brake lamp. Any new suggestions? Or is it linked to the left front parking lamp? Have no idea how this all is linked to pulling a steering column!

Thanks
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Old 03-19-2017, 04:12 PM   #34
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Re: Signal lamps help again

I have power at the signal switch wiring for the rear lamps with flashers on. With flashers on it blinks at the signal switch wiring yellow, green and white. At the rear wiring going into the dash, it blinks at the yellow wiring and dark green and constant power to brown. Does not flash with just blinkers on going into dash.
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Old 03-19-2017, 04:16 PM   #35
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Re: Signal lamps help again

Update only have no rear lamps with lights on? Getting close.
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Old 03-19-2017, 06:50 PM   #36
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Re: Signal lamps help again

Ok, here is what I think you have said.
4 way flashers on, you get flash on yellow and green at the turn signal switch...what happens at the rear lights?
Did you use a test light on the bulb pins at the rear lights?

If no power to right rear light pin with test light then test with test light at light harness where it plugs in at last bed crossmember

If power and the light does not light up or flash then check for ground.
Check for bad ground and right rear by jumping a ground wire from frame to side of bulb and check bulb pins with test light.
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Old 03-19-2017, 06:55 PM   #37
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Re: Signal lamps help again

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Ok, here is what I think you have said.
4 way flashers on, you get flash on yellow and green at the turn signal switch...what happens at the rear lights?
Did you use a test light on the bulb pins at the rear lights?

If no power to right rear light pin with test light then test with test light at light harness where it plugs in at last bed crossmember

If power and the light does not light up or flash then check for ground.
Check for bad ground and right rear by jumping a ground wire from frame to side of bulb and check bulb pins with test light.

At this point got everything working except both rear lamps when light switch is on for night driving. Signals and brake lamps working.
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Old 03-19-2017, 06:58 PM   #38
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Re: Signal lamps help again

Ok, so that is the brown wire which also powers the front marker lights, I don't know is that fused? Could it have blown when you were working on the short at the left front?
Did you test the rear light pins to see if you have power to the pin?
Its unlikely but you could have 2 bad bulbs from the short in the front, its the same circuit.
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Old 03-19-2017, 07:17 PM   #39
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Re: Signal lamps help again

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Ok, so that is the brown wire which also powers the front marker lights, I don't know is that fused? Could it have blown when you were working on the short at the left front?
Did you test the rear light pins to see if you have power to the pin?
Its unlikely but you could have 2 bad bulbs from the short in the front, its the same circuit.
I'll check. Thanks

I did have power at the Brown wire going into the firewall to for the rear lamps. But I will check everything.

Last edited by 66clow; 03-19-2017 at 07:24 PM.
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Old 03-26-2017, 09:20 AM   #40
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Re: Signal lamps help again

Here is where I am. Checking at the firewall wire going to rear. I have power at the Brown wire. Yellow wire have constant power and blinks with signal on. Dark green the power on constant and signals but is weak lamp with signal on but bright with hazard on. With light switch on both dk green and yellow bright, no power on Brown wire. If that is how it works?

LR lamp blinks and stop light. Nothing on right. Light switch on no difference at fire wall yellow green Brown all have power. Unsure if that is how it works.
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Old 03-26-2017, 10:03 AM   #41
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Re: Signal lamps help again

I think you have 2 problems.
Problem 1:
Week lamp at green wire and strong on 4way at firewall is from contacts in turn signal switch.
Disassemble the switch, clean and lube it.


Problem 2:
1. Bad ground at right rear taillight housing or no power to the housing.
Test: Use test light with a known good ground to pins in the housing then post the results.
If power to pins test the bulb in the other side. and
With bulb installed, use a wire from known ground to brass on side of bulb, if this corrects the problem then the housing is not grounded, if it doesn't correct it then the pins in the housing are not contacting the bulb. The springs behind the pins are bad.

Test problem 2 and correct first. You should get at least strong 4 way flash when this is corrected but possibly not signal and stop because of weak signal at firewall.
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Old 03-26-2017, 10:04 AM   #42
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Re: Signal lamps help again

I assume you r test results were from you testing the rear light plug which is above the gas pedal, right?
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Old 03-26-2017, 10:13 AM   #43
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Re: Signal lamps help again

Here is a description of the rear turn signal light paths

Turn signal
It flashes on either side because power originates from the turn signal flasher and power is connected to either side through the turn signal switch and onto the left or right lamp, the flash comes from the flasher, a load is created which generates heat inside the flasher, the bi-metal contact heats up, bends and the light goes out, the metal cools and the light goes on. Same thing happens on the other side except a different contact is used in the turn signal switch.
4 way
This is a separate power path through the 4 way flasher and connects directly to the tail light lamp wires on other side of turn signal switch (bypasses the contacts for turn signals) so they 4 way on both sides no mater signal switch position.
Stop lamps
bypass turn signal switch for rear lamps. Front will flash while brakes applied but rear will not.

Maybe that helps to understand the system.
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Old 03-26-2017, 10:19 AM   #44
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Re: Signal lamps help again

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I assume you r test results were from you testing the rear light plug which is above the gas pedal, right?
Correct. I am showing power at the RR tail lamp when I use my test light. But I'll do the checks.
Got a feeling my problem may be the signal switch since that is really the only thing that was twisted around a bit when I pulled the steering column. Ugh! Thanks
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Old 03-26-2017, 10:24 AM   #45
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Re: Signal lamps help again

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Here is where I am. Checking at the firewall wire going to rear. I have power at the Brown wire. Yellow wire have constant power and blinks with signal on. Dark green the power on constant and signals but is weak lamp with signal on but bright with hazard on. With light switch on both dk green and yellow bright, no power on Brown wire. If that is how it works?

LR lamp blinks and stop light. Nothing on right. Light switch on no difference at fire wall yellow green Brown all have power. Unsure if that is how it works.
I wonder if your describing this correctly.
Here is what you should have.

Lights off
No power to any thing at rear
Turn signal switched to left, should give power to yellow and then flash.
Turn signal switched to right, should give power to green and then flash.
Push on brake pedal and yellow and green should have power, if a signal switch is on that one will flash

Lights on
Everything the same as above except power to the brown wire. Which gives tail lamps, side marker lamps and license lamp power.
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Old 03-26-2017, 11:18 AM   #46
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Re: Signal lamps help again

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Originally Posted by randy500 View Post
I wonder if your describing this correctly.
Here is what you should have.

Lights off
No power to any thing at rear
Turn signal switched to left, should give power to yellow and then flash.
Turn signal switched to right, should give power to green and then flash.
Push on brake pedal and yellow and green should have power, if a signal switch is on that one will flash

Lights on
Everything the same as above except power to the brown wire. Which gives tail lamps, side marker lamps and license lamp power.
I need to go verify but have power to brown when light switch off and no power with it on which I guess should be switched? But now I'm confused lol. I'll do some checking again and confirm what I have.
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Old 03-26-2017, 11:26 AM   #47
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Re: Signal lamps help again

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I need to go verify but have power to brown when light switch off and no power with it on which I guess should be switched? But now I'm confused lol. I'll do some checking again and confirm what I have.
The brown wire also lights up the front lights so you shouldn't have power to it with the headlight switch off.
The brown wire does not go through the turn signal switch and gets power from the headlight switch.
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Old 03-26-2017, 11:47 AM   #48
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Re: Signal lamps help again

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The brown wire also lights up the front lights so you shouldn't have power to it with the headlight switch off.
The brown wire does not go through the turn signal switch and gets power from the headlight switch.
Ok so could be the headlights switch or some where along the brown wire.
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Old 03-26-2017, 12:09 PM   #49
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Re: Signal lamps help again

Are you saying brown has power when switxh is off?
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Old 03-26-2017, 12:10 PM   #50
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Re: Signal lamps help again

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Are you saying brown has power when switxh is off?

Yes, but I'll go out this afternoon to confirm
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