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Still no back up light??

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Old Apr 12, 2009 | 10:32 PM
  #1  
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Still no back up light??

Well I starting tracing the wires back starting at the back up lights. I've traced it all the way up to the green plug on the left fenderwell toward the firewall and have no power. There it goes into the fuse box but I don't have any power at the plug in the middle of the firewall behind the air cleaner and the goes down to the neutral saftey switch, so where do I need to go from here??
 
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Old Apr 15, 2009 | 01:02 PM
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From: LaGrange
Originally Posted by alconk
Well I starting tracing the wires back starting at the back up lights. I've traced it all the way up to the green plug on the left fenderwell toward the firewall and have no power. There it goes into the fuse box but I don't have any power at the plug in the middle of the firewall behind the air cleaner and the goes down to the neutral saftey switch, so where do I need to go from here??

Ok,
__presuming that you are working on a 79'-100, with an auto-tranz.

Does the B-lights/windshield wiper-pump fuse has power?
(F-11 in fusebox)

Corrosion of the fuse or terminnals can cause contact prob's as well.
Give a good cleaning of F-box terms, then check to see if it is reciving
power there. If all checks out, put a new fuse in; & check lights again.
 
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Old Apr 15, 2009 | 01:21 PM
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Yes I have power there and my washer pump works fine??
 
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Old Apr 15, 2009 | 02:39 PM
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Ok,
__the washer pump & the reverse lights are powered by the same fuse.
So now we know that they are reciving power.

You need to check to see if the tranz
neutral/reverse switch is getting power to it.

It is mounted on diver's side of the tranz with the shifter linkage.
The wires for it, are on passinger side next to the blower-box.
Within main harness which comes out of the fire-wall.
(look for a gray connector.)

It has four wires, the two you are looking for are:
(whitewith purple stripe power in.)
(black with red stripe is out, to reverse lights.)
 
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Old Apr 15, 2009 | 06:51 PM
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Originally Posted by crazedfox
Ok,
__the washer pump & the reverse lights are powered by the same fuse.
So now we know that they are reciving power.

You need to check to see if the tranz
neutral/reverse switch is getting power to it.

It is mounted on diver's side of the tranz with the shifter linkage.
The wires for it, are on passinger side next to the blower-box.
Within main harness which comes out of the fire-wall.
(look for a gray connector.)

It has four wires, the two you are looking for are:
(whitewith purple stripe power in.)
(black with red stripe is out, to reverse lights.)
Very good..... but no power??? Well kinda only 2.6V?? Were getting somewhere though, keep it up..
 
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Old Apr 15, 2009 | 09:58 PM
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Ok,
__where did you get your reading?

At the switch?
Or
At the connector?

Which wire?
With the white with purple stripe.
(or)
The black with red stripe?

Did you pull back the wire's shielding
(plastic coat) to take the reading?
.
 
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Old Apr 15, 2009 | 11:23 PM
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Originally Posted by crazedfox
Ok,

__where did you get your reading?

At the switch?
Or
At the connector?

Which wire?
With the white with purple stripe.
(or)
The black with red stripe?

Did you pull back the wire's shielding
(plastic coat) to take the reading?

.
I got the reading at the grey plug, white w/purple stripe. I didn't unplug it I just poked the probe in touched the metal part.
 
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Old Apr 15, 2009 | 11:24 PM
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Actually I probbed the four wires but only the white/purple gave any reading.
 
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Old Apr 16, 2009 | 11:15 PM
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Ok,
__I replied last night.
But the F**k**g site mantainance erased it!
& it was shut down for some time.

Allright that's over.
What you need to do is do a short test on the
white with purple stripe wire.
To find out if there is any breaks/shorts in this wire.

(do you have a mutimeter with a continuity setting?)

Let me know.
 
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Old Apr 16, 2009 | 11:23 PM
  #10  
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Originally Posted by crazedfox
Ok,
__I replied last night.
But the F**k**g site mantainance erased it!
& it was shut down for some time.

Allright that's over.
What you need to do is do a short test on the
white with purple stripe wire.
To find out if there is any breaks/shorts in this wire.

(do you have a mutimeter with a continuity setting?)

Let me know.
Yes I do..
 
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Old Apr 16, 2009 | 11:51 PM
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From: LaGrange
Good,
__take a 12-14 foot wire wrap it @ least 3 times
around 1 of your testers probes tightly.
Connect the other end of your new test lead wire to
the white with purple stripe inside your fuse box.

You can do this by taking out the 2 screws that
hold the box up. Locate the wire with the
white with purple stripe inside, then make a soild
connection as close to the fuse terminnal as possible.

Then pull back the plastic cover on the wire with
the white with purple stripe up near the gray
connector in the engine bay & take your reading there.

Gotta, sleep.
Later.
 
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Old Apr 17, 2009 | 12:39 PM
  #12  
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Originally Posted by crazedfox
Good,
__take a 12-14 foot wire wrap it @ least 3 times
around 1 of your testers probes tightly.
Connect the other end of your new test lead wire to
the white with purple stripe inside your fuse box.

You can do this by taking out the 2 screws that
hold the box up. Locate the wire with the
white with purple stripe inside, then make a soild
connection as close to the fuse terminnal as possible.

Then pull back the plastic cover on the wire with
the white with purple stripe up near the gray
connector in the engine bay & take your reading there.

Gotta, sleep.
Later.
Ok... 11.74V that's just with the key in the on position.
 
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Old Apr 17, 2009 | 02:45 PM
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Um,
__not a voltage test.

You need to do a continuity test.
 
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Old Apr 17, 2009 | 06:53 PM
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Originally Posted by crazedfox
Um,
__not a voltage test.

You need to do a continuity test.
Whoops, will have to wait till tomorrow. But tell me what you think, if I have lets say 12 volts by doing that doesn't that tell me I might have a bad ground?? I'll still check that tomorrow or maybe tonight when I get off work..
 
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Old Apr 17, 2009 | 07:28 PM
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Originally Posted by crazedfox
Um,
__not a voltage test.

You need to do a continuity test.
I was able to get away for a few minutes and done the test. 0.0 ohms is what I came up with. No break in the wire.
 
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