Tail light won't work, tried a couple new bulbs, connection looks solid
#16
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Both. But mainly the cruise light. The brake light doesn't come on but the bulb will light up when I turn it back and forth within the housing and then it'll stay lit until the brakes are released.
When the brake is depressed again, the brake bulb won't light, so I have to turn it again, etc.
The cruise light/tail light bulb doesn't light no matter what I try.
Now is as good a time as any to try and figure out how to use the multimeter I bought in order to test for voltage :-o
When the brake is depressed again, the brake bulb won't light, so I have to turn it again, etc.
The cruise light/tail light bulb doesn't light no matter what I try.
Now is as good a time as any to try and figure out how to use the multimeter I bought in order to test for voltage :-o
#17
Nerd Herder
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Check your Main chassis grounds.
Then run a continuity test ground to socket with a multi meter.
You're on the right track.
Then run a continuity test ground to socket with a multi meter.
You're on the right track.
#18
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So I undid the white plug (top pic) where the main harness feeds into the bulb holder bracket (bottom pic) and all the female pins register a "pulse" on the multimeter.
I then replug the white plug together and test for a pulse on the bulb holder bracket itself and when I test each individual bulb holder (red on the bulb holder piece that comes in contact with the bottom tip of the bulb itself and black on the bulb holder bracket) and all the individual bulb holders register a pulse except the brake light and the cruise light/tail light which corresponds to the two that aren't working.
So my conclusion is that what I need is the wiring originating at the second half the white plug until the connectors that connect to the bulb holder bracket but I don't know what this is called ... anyone know what I should ask for? When I call places for these types of parts if you don't get the terminology exactly right you end up with the wrong thing or they can't find it at all, thanks in advance
I then replug the white plug together and test for a pulse on the bulb holder bracket itself and when I test each individual bulb holder (red on the bulb holder piece that comes in contact with the bottom tip of the bulb itself and black on the bulb holder bracket) and all the individual bulb holders register a pulse except the brake light and the cruise light/tail light which corresponds to the two that aren't working.
So my conclusion is that what I need is the wiring originating at the second half the white plug until the connectors that connect to the bulb holder bracket but I don't know what this is called ... anyone know what I should ask for? When I call places for these types of parts if you don't get the terminology exactly right you end up with the wrong thing or they can't find it at all, thanks in advance
#21
Addict
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For stuff like this a DMM can show a voltage where there really is no circuit that will provide current. It is way better to test with a test lamp that pulls a few watts. That is to say a digital multimeter might show 12 volts but if you put a bulb on it, it won't light up. The voltage is there but at no load and though a bad connection, bad switch, etc.
#23
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Got the 944online bulb holder in, electro-dusted everything, applied dielectric grease, still no joy.
I trace the harness all the way back to a cluster emanating from roof of the the driver's wheel well (where my ability to trace further ceases), the only branches are for the left (driver's tail light assembly) and a couple branch offs behind the rear seats (not sure what those are for)
In other words there's no place to cleanly substitute a replacement harness.
Before I take it to the shop, I may have mixed up the 3 larger bulbs. For the running light it's a smaller bulb so I know where that goes but are the three larger bulbs that are all the same size also the same wattage and if not, which one goes where? (if mixing wattages could even cause the bulb in that particular socket not to function)
I trace the harness all the way back to a cluster emanating from roof of the the driver's wheel well (where my ability to trace further ceases), the only branches are for the left (driver's tail light assembly) and a couple branch offs behind the rear seats (not sure what those are for)
In other words there's no place to cleanly substitute a replacement harness.
Before I take it to the shop, I may have mixed up the 3 larger bulbs. For the running light it's a smaller bulb so I know where that goes but are the three larger bulbs that are all the same size also the same wattage and if not, which one goes where? (if mixing wattages could even cause the bulb in that particular socket not to function)
Last edited by Mister Quickie; 09-19-2015 at 10:04 PM.
#24
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One of the fuses (#41) was blown. Supposed to take a 7.5A and the PO put in a 20A.
Replaced the fuse and turned on the lights, saw the light flicker and it blew the fuse.
I compared all the bulbs to the sockets and they all match so I'm going to compare with the wiring on the left/driver's rear tail light assembly to see if there are any mismatches
Replaced the fuse and turned on the lights, saw the light flicker and it blew the fuse.
I compared all the bulbs to the sockets and they all match so I'm going to compare with the wiring on the left/driver's rear tail light assembly to see if there are any mismatches
#25
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Stumped
I removed the assembly to left side in which all the lights work.
I compared the wiring in the back and made sure the right/problem side wiring matched the left/good side wiring.
I made sure each bulb was correct for each socket on both sides (all are 21 except the running lights which are 5).
I ran down the entire fuse box to make sure each fuse was the rights amperage as indicated on the mapping.
I put in a 7.5A fuse in slot 41 for the rear right/passenger running light.
I turned on the car to test,
Brake lights fine on both sides.
Reverse lights fine on both sides.
Turn signal still only works on the left/drivers side. Tried a new bulb, still no joy.
Turned on the lights, same as before, the right/passengers side light flickered and when I checked the fuse (#41), it had blown. The only difference this time is that now the running light on the left/drivers side no longer works and it did before. I checked the fuse box for the left/drivers side running light and it has not blown.
Time to throw in the towel and take it to the shop?
I removed the assembly to left side in which all the lights work.
I compared the wiring in the back and made sure the right/problem side wiring matched the left/good side wiring.
I made sure each bulb was correct for each socket on both sides (all are 21 except the running lights which are 5).
I ran down the entire fuse box to make sure each fuse was the rights amperage as indicated on the mapping.
I put in a 7.5A fuse in slot 41 for the rear right/passenger running light.
I turned on the car to test,
Brake lights fine on both sides.
Reverse lights fine on both sides.
Turn signal still only works on the left/drivers side. Tried a new bulb, still no joy.
Turned on the lights, same as before, the right/passengers side light flickered and when I checked the fuse (#41), it had blown. The only difference this time is that now the running light on the left/drivers side no longer works and it did before. I checked the fuse box for the left/drivers side running light and it has not blown.
Time to throw in the towel and take it to the shop?
#26
Drifting
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Sounds like a short to ground by the spare tire.
This is a sweet little tool that can determine the amperage capacity of a circuit from Beckmann Technology http://bluelinkdiag.com/probe.aspx
This is a sweet little tool that can determine the amperage capacity of a circuit from Beckmann Technology http://bluelinkdiag.com/probe.aspx
#27
#28
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If you have to turn the bulb in the socket, it isn't getting a good ground to the outside of the bulb.(brass? case? try wrapping the outside of the bulb with a short length of tinfoil to take up any gaps that might be between the sides of the bulb and the socket. Otherwise, it sure sounds like a short in the system somewhere that keeps blowing the fuse. Do you get good current with a test light all the way down the harness going to the taillight when the circuit is on? If no juice halfway down the power lead, then the problem is back toward the cluster and the fuse block. If you get good power, down at the white connector...the the problem is either in the taillight assembly or the harness going to it. Hope this helps some.
#29
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Used a test light:
- No power going to either rear running light bulb holder
- No power going to either rear running light (white) female connector from harness
- No power going to the fuse box for either rear running light
All the other lights passed the test for power in all categories above
Isn't the fuse box the first stop, What could be wrong?
- No power going to either rear running light bulb holder
- No power going to either rear running light (white) female connector from harness
- No power going to the fuse box for either rear running light
All the other lights passed the test for power in all categories above
Isn't the fuse box the first stop, What could be wrong?
#30
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In case it was the running light switch I tested the front headlights with the test light by touching the fuses and they both went out so now I have no running lights, front or rear and the fuses light the test light for the front ones but the fuses for the rear running lights don't light the test light