Both tail lights out....which fuse?
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From: Massachusetts
Both tail lights out....which fuse?
The central warning light came on and indicated a problem with the tail lights. Indeed, both of them were unlit. It is not clear to me which fuse to check. The fuse diagrams for the 1981 MY don't show this (or I am simply not seeing that information). Fuses 9, 10, 31, and 33 are used for other lights in the rear cluster.
Thanks in advance for your help.
Regards,
John
1981 928 Chiffon White over Cashmere A/T (127k)
Thanks in advance for your help.
Regards,
John
1981 928 Chiffon White over Cashmere A/T (127k)
Thread Starter
Instructor
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From: Massachusetts
Thanks Mrmerlin! Both lamps went out simultaneously which is why I thought it might be a fuse. I'll clean the connections tomorrow and reply back.
Regards,
John
1981 928 Chiffon White over Cashmere A/T (127k)
Regards,
John
1981 928 Chiffon White over Cashmere A/T (127k)
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From: Massachusetts
Thanks everyone. Fuse #10 is good. Brake lights and tail lights are working again. Since this is an intermittent issue, I will check all lamp connections and deoxit as suggested by Mrmerlin.
Regards,
John
1981 928 Chiffon White over Cashmere A/T (127k)
Regards,
John
1981 928 Chiffon White over Cashmere A/T (127k)
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From: Philly PA
lamp controller is bolted to the top of the CE panel
you might find corroded pins
NOTE as Alan said it could also be a dirty fuse connection add deoxit to all the fuses as well
you might find corroded pins
NOTE as Alan said it could also be a dirty fuse connection add deoxit to all the fuses as well
Last edited by Mrmerlin; Oct 15, 2020 at 12:10 PM.
Thread Starter
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From: Massachusetts
Mrmerlin...I'm just getting back to this electrical maintenance task. I didn't even know there was a lamp controller but I've found it where you described. Should i be able to work the connector free in place without unbolting anything? It looks pretty tight to me.
I did apply deoxit to the fuse connections but erratic warning light behavior still persists. Might it be worth a try to deoxit the CW connectors as well which I believe are under the dead pedal?
Regards,
John
1981 AT
I did apply deoxit to the fuse connections but erratic warning light behavior still persists. Might it be worth a try to deoxit the CW connectors as well which I believe are under the dead pedal?
Regards,
John
1981 AT
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From: Philly PA
it will be easier to work on if the parcel tray is out and the wood panel is out.
disconnect the battery first.
then use a thin screw driver to work the connector off the module.
NOTE Its also prudent to put deoxit on all of the connectors along the bottom of the CE panel ,
be careful as some of the wires can pop out of their connector housings.
While your at the CE panel test for power to the tail lamps ,
if you have it then the wire may be broken at the main lamp connector behind the RR interior liner
disconnect the battery first.
then use a thin screw driver to work the connector off the module.
NOTE Its also prudent to put deoxit on all of the connectors along the bottom of the CE panel ,
be careful as some of the wires can pop out of their connector housings.
While your at the CE panel test for power to the tail lamps ,
if you have it then the wire may be broken at the main lamp connector behind the RR interior liner
Last edited by Mrmerlin; Nov 2, 2020 at 06:50 PM.
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Electron Wrangler
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A loose/poor connection is actually more likely at the bulb (e.g. they occasionally have a fault that you don't notice and that self corrects). I'd clean the connections and perhaps replace all the bulbs. - cheap insurance...
Alan
Alan
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I will say that I have had good results from putting a drop or two of Deoxit on every connection on the CE panel, even going as far as flipping the panel forward and going across all the connections on the rear, along with wiggling them a tiny bit after putting the Deoxit on them.
I've had lights start functioning that were inoperable when I left the garage the prior weekend. (Walking into the garage and finding the left side turn signals on was puzzling, until I realized that I'd bumped the selector and over the length of the week they had regained function...)
I've had lights start functioning that were inoperable when I left the garage the prior weekend. (Walking into the garage and finding the left side turn signals on was puzzling, until I realized that I'd bumped the selector and over the length of the week they had regained function...)
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From: Massachusetts
I have separated the connectors from the lamp control module and applied Deoxit to the 12 pins as you suggested. There was significant corrosion which you suspected. Unfortunately, the 12 connectors slipped out of the black plastic guide, and I need help figuring which connector goes on which pin. I see that the pins are numbered but the connectors are not. I've tried following the Part V current flow diagram but that is a skill I have not yet acquired. Is there a wire color reference guide that could help me match them up correctly?
Regards,
John
Regards,
John
Electron Wrangler
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Pin 1 - Black/Red
Pin 2 - Brown
Pin 3 - Grey/Red (rear right marker - out)
Pin 4 - Grey/Black (rear left marker - out)
Pin 5 - Grey/Red (front right marker - in)
Pin 6 - Black (to central warning)
Pin 7 - Grey/Black (front left marker - in)
Pin 8 - Red/White
Pin 9 - Black/Red (Brake Right)
Pin 10 - Black (from Fuse 7)
Pin 11 - Black/Blue
Pin 12 - Black/Red (Brake Left)
Alan
Pin 2 - Brown
Pin 3 - Grey/Red (rear right marker - out)
Pin 4 - Grey/Black (rear left marker - out)
Pin 5 - Grey/Red (front right marker - in)
Pin 6 - Black (to central warning)
Pin 7 - Grey/Black (front left marker - in)
Pin 8 - Red/White
Pin 9 - Black/Red (Brake Right)
Pin 10 - Black (from Fuse 7)
Pin 11 - Black/Blue
Pin 12 - Black/Red (Brake Left)
Alan
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I've serviced the lamp control module and reconnected the 12 pin sleeves in the correct order as noted by Alan. However, there are still a couple of quirky happenings:
1. About 5 seconds after turning on the parking lights and/or headlights, the CWS red light illuminates. This can be reset by pressing the CWS button
2. The CWS red light illuminates at the appropriate time when the fuel level is low. I was always able to reset this by pressing the CWS button but now it remains lit until I refuel.
I might try re-applying deoxit to pin #6 as well as the connector sleeve for that one but after that I am lost.
As always, I welcome and appreciate all suggestions!
Regards,
John
1. About 5 seconds after turning on the parking lights and/or headlights, the CWS red light illuminates. This can be reset by pressing the CWS button
2. The CWS red light illuminates at the appropriate time when the fuel level is low. I was always able to reset this by pressing the CWS button but now it remains lit until I refuel.
I might try re-applying deoxit to pin #6 as well as the connector sleeve for that one but after that I am lost.
As always, I welcome and appreciate all suggestions!
Regards,
John