Halogens will wear out the switch for sure, but they will blow the
internal breaker before smoking out the wires. You have a short still
or the plug is bad inside so the contact to the switch isn't tight. A
arc will heat it up fast and smoke it.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Aug./05 http://www.imagestation.com/album/in...?id=2120343242
(More Off Road album links at bottom of the view page)


"randallbrink@adelphia.net" wrote:
>
> Jim:
>
> Thanks. I did it--tracing the wires wherever I could access them, and
> also checking resistence with the tester on all wiring. I know the
> switch splice is clean; believer the rest of the wiring to also.
>
> I tested again and isolated the tiny emission of smoke to the new
> headlight switch. The back of the switch gets too hot to touch,
> especially around the ceramic shield and dome light actuator switch.
>
> I have developed a new theory, with the help of an article by Mike
> D'Ambrogia, lined on the IFSJA website, that the Halogen headlights
> with which this GW is equipped are at fault. They draw too much power
> and overheat the switch. I am fairly certain that the 1984 Grand
> Wagoneer was NOT originally equipped with these much brighter lights.
>
> RB

 

Halogens will wear out the switch for sure, but they will blow the
internal breaker before smoking out the wires. You have a short still
or the plug is bad inside so the contact to the switch isn't tight. A
arc will heat it up fast and smoke it.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Aug./05 http://www.imagestation.com/album/in...?id=2120343242
(More Off Road album links at bottom of the view page)


"randallbrink@adelphia.net" wrote:
>
> Jim:
>
> Thanks. I did it--tracing the wires wherever I could access them, and
> also checking resistence with the tester on all wiring. I know the
> switch splice is clean; believer the rest of the wiring to also.
>
> I tested again and isolated the tiny emission of smoke to the new
> headlight switch. The back of the switch gets too hot to touch,
> especially around the ceramic shield and dome light actuator switch.
>
> I have developed a new theory, with the help of an article by Mike
> D'Ambrogia, lined on the IFSJA website, that the Halogen headlights
> with which this GW is equipped are at fault. They draw too much power
> and overheat the switch. I am fairly certain that the 1984 Grand
> Wagoneer was NOT originally equipped with these much brighter lights.
>
> RB

 

Halogens will wear out the switch for sure, but they will blow the
internal breaker before smoking out the wires. You have a short still
or the plug is bad inside so the contact to the switch isn't tight. A
arc will heat it up fast and smoke it.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Aug./05 http://www.imagestation.com/album/in...?id=2120343242
(More Off Road album links at bottom of the view page)


"randallbrink@adelphia.net" wrote:
>
> Jim:
>
> Thanks. I did it--tracing the wires wherever I could access them, and
> also checking resistence with the tester on all wiring. I know the
> switch splice is clean; believer the rest of the wiring to also.
>
> I tested again and isolated the tiny emission of smoke to the new
> headlight switch. The back of the switch gets too hot to touch,
> especially around the ceramic shield and dome light actuator switch.
>
> I have developed a new theory, with the help of an article by Mike
> D'Ambrogia, lined on the IFSJA website, that the Halogen headlights
> with which this GW is equipped are at fault. They draw too much power
> and overheat the switch. I am fairly certain that the 1984 Grand
> Wagoneer was NOT originally equipped with these much brighter lights.
>
> RB

 

The ceramic collar holds a wire coil, that is the attenuator for the dome
and instrument panel lights. An attenuator converts unwanted voltage into
heat. This is not the best design, but it is the simplest. It may smoke
after installation, and it may become hot with the dome and instrument panel
lights dimmed, but I don't think that "extremely hot" is a description of
proper behavior. The collar is ceramic so that it can stand the heat. That
appears to be a separate issue from the fuse blowing on the dim headlight
setting. Can you disconnect the dome light circuit, and try again? Can you
rig up an ammeter in the circuit? Clip on ammeters are great, and make
great gifts too.

Earle

<randallbrink@adelphia.net> wrote in message
news:1133823547.810292.75490@g47g2000cwa.googlegro ups.com...
> Update--
>
> Smoke was coming from the new light switch. I unhooked the connector
> after seeing wisps of smoke. The ceramic collar that holds the dome
> light "on/off" switch became extremely hot. I now suspect a short in
> the dome light circuit, but there could be a problem with any circuit
> on that switch.
>

 

The ceramic collar holds a wire coil, that is the attenuator for the dome
and instrument panel lights. An attenuator converts unwanted voltage into
heat. This is not the best design, but it is the simplest. It may smoke
after installation, and it may become hot with the dome and instrument panel
lights dimmed, but I don't think that "extremely hot" is a description of
proper behavior. The collar is ceramic so that it can stand the heat. That
appears to be a separate issue from the fuse blowing on the dim headlight
setting. Can you disconnect the dome light circuit, and try again? Can you
rig up an ammeter in the circuit? Clip on ammeters are great, and make
great gifts too.

Earle

<randallbrink@adelphia.net> wrote in message
news:1133823547.810292.75490@g47g2000cwa.googlegro ups.com...
> Update--
>
> Smoke was coming from the new light switch. I unhooked the connector
> after seeing wisps of smoke. The ceramic collar that holds the dome
> light "on/off" switch became extremely hot. I now suspect a short in
> the dome light circuit, but there could be a problem with any circuit
> on that switch.
>

 

The ceramic collar holds a wire coil, that is the attenuator for the dome
and instrument panel lights. An attenuator converts unwanted voltage into
heat. This is not the best design, but it is the simplest. It may smoke
after installation, and it may become hot with the dome and instrument panel
lights dimmed, but I don't think that "extremely hot" is a description of
proper behavior. The collar is ceramic so that it can stand the heat. That
appears to be a separate issue from the fuse blowing on the dim headlight
setting. Can you disconnect the dome light circuit, and try again? Can you
rig up an ammeter in the circuit? Clip on ammeters are great, and make
great gifts too.

Earle

<randallbrink@adelphia.net> wrote in message
news:1133823547.810292.75490@g47g2000cwa.googlegro ups.com...
> Update--
>
> Smoke was coming from the new light switch. I unhooked the connector
> after seeing wisps of smoke. The ceramic collar that holds the dome
> light "on/off" switch became extremely hot. I now suspect a short in
> the dome light circuit, but there could be a problem with any circuit
> on that switch.
>

 

It could well be that, because the switch was newly installed, the
little wisp of smoke was just the switch getting "burned in" and
perhaps there were traces of oil on the ceramic heat sink. I also
noticed this morning, that I did have the dome and courtesy lights
switched to "on" which may have contributed.

All is seemingly in order now, with thanks to all here who guided me
through this frustrating but interesting project.

RB

 

It could well be that, because the switch was newly installed, the
little wisp of smoke was just the switch getting "burned in" and
perhaps there were traces of oil on the ceramic heat sink. I also
noticed this morning, that I did have the dome and courtesy lights
switched to "on" which may have contributed.

All is seemingly in order now, with thanks to all here who guided me
through this frustrating but interesting project.

RB

 

It could well be that, because the switch was newly installed, the
little wisp of smoke was just the switch getting "burned in" and
perhaps there were traces of oil on the ceramic heat sink. I also
noticed this morning, that I did have the dome and courtesy lights
switched to "on" which may have contributed.

All is seemingly in order now, with thanks to all here who guided me
through this frustrating but interesting project.

RB

 

You're no doubt right. Lurking in the background of all this is the
thought that I may not have corrected the condition that caused the
fire in the first place. Seeing even a wisp of smoke was enough to
cause me to panic after that,

I believe I will start over again tracing power to that switch and
recheck the resistence in the wires on the switch

RB