FJ60 Speedhut Gauges/ climate control bulb wiring (1 Viewer)

[Hojack]

Need some help understanding my wiring for the climate control and speedometer/ gauge cluster lighting. My climate control was not lighting up so removed the cover and found it lit very dim even with the dimmer switch turned up all the way. When I removed the bulb I found the backlighting for the speedometer/ dash cluster lights go out to. Reinstall the bulb and the backlighting turns on. Very confused that the bulb is playing a part of the dash lighting circuit... hmm??? I converted to Speedhut Gauges and am curious if there is something causing the trouble. Also does anybody have any idea where to source these bulbs. Went to several auto parts stores and no dice.

1-1/8” in length
Only number on bulb A12V2W

 

[tmxmotorsports]

Wish i could help but the 60 that i swapped isn't here and the 2 60s i am working on are kinda apart right now neither have speed hut gauges. I am almost certain that they shouldn't go out when you take the bulb out it may be in your wiring on the speed hut gauges.

 

[Hojack]

I’ve got 12V to top of bulb terminal. If I jumper the Speedhut gauges light up.

 

[Hojack]

Wish i could help but the 60 that i swapped isn't here and the 2 60s i am working on are kinda apart right now neither have speed hut gauges. I am almost certain that they shouldn't go out when you take the bulb out it may be in your wiring on the speed hut gauges.

It’s strange, the power is going through the bulb to power the Speedhut Gauges. Guess I’m going to need to remove the instrument panel. I’m cannot see what color wires go to the climate control bulb.

 

[OSS]

Supposedly Toyota still sells it. Check.
It's only $32.

Not sure how that bulb is wired, but it may be in series like those cheapo irritating Xmas tree lights where if one bulb goes out, they all go out.

 

[Hojack]

Thanks @OSS
yikes highway robbery!
Looks like the Speedhut Gauges have an inverter and dimmer switch to convert DC to AC for the backlighting. I think the bulb is so dim because it’s getting AC power. Jumpered or with the bulb in the dimmer switch works for the Speedhut backlighting. @FJ60Cam I need a little help here.

 

[60 toy ota]

I've currently got my dash all apart, let me know if you need pics

 

[FJ60Cam]

Thanks @OSS
yikes highway robbery!
Looks like the Speedhut Gauges have an inverter and dimmer switch to convert DC to AC for the backlighting. I think the bulb is so dim because it’s getting AC power. Jumpered or with the bulb in the dimmer switch works for the Speedhut backlighting. @FJ60Cam I need a little help here.

How do you have the Speedhuts wired to receive the headlight-on signal?

The Speedhut dimmer should operate independently of the factory dimmer. Neither should control the other.

 

[Hojack]

I need to get power for the climate control after the headlight/ running light switch that goes to the running lights as they are all working. The climate control shouldn’t be on the backlighting Speedhut Gauge circuit. Need help locating the climate control wires and running light wire after the headlight/ running light switch.

 

[Hojack]

How do you have the Speedhuts wired to receive the headlight-on signal?

The Speedhut dimmer should operate independently of the factory dimmer. Neither should control the other.

Yes, the headlight signal operates the backlighting just fine. I only have the Speedhut dimmer. Removed the stock dimmer as it was not needed. I posted above what I think my problem is. I just need to locate the proper wires. Is the climate control wire in series like the Christmas tree lighting like @OSS mentioned? Wondering why the bulb even if it’s not on powers the Speedhut backlighting... I think it’s getting AC power after the inverter.
I need to get some dinner...

 

[Hojack]

@60 toy ota
Need help locating the climate control wires and running light wire after the headlight/ running light switch.

 

[OSS]

The wiring diagram for the gauge lights etc, also showing the rheostat dimmer is in the wiring diagram in the back of the Body FSM. The heater slider bulb isn't specifically called out in the drawing, but it's definitely part of that circuit. For what it's worth, here's the schematic. I've pointed out where the rheostat lives (lived) in the circuit and highlighted where 12V+ should be coming from.
Maybe one of the countless green wires.

 

[Hojack]

The wiring diagram for the gauge lights etc, also showing the rheostat dimmer is in the wiring diagram in the back of the Body FSM. The heater slider bulb isn't specifically called out in the drawing, but it's definitely part of that circuit. For what it's worth, here's the schematic. I've pointed out where the rheostat lives (lived) in the circuit and highlighted where 12V+ should be coming from.
Maybe one of the countless green wires.


View attachment 2131286

Is the heater control circled in yellow the bulb for the climate control?

 

[OSS]

I think so...

 

[Hojack]

@FJ60Cam May need some assistance. I don’t think I tied any other circuits off the Speedhut inverter and dimmer. Wondering why my climate control bulb is playing a part of the circuit. Last night I pulled the bulb from the dome light and installed it. The bulb did not light up but the Speedhut Gauge backlighting did...

 

[OSS]

I'd rethink the grounding connection for the SpeedHut gauges. When wonky stuff like this happens in the cruiser, it's often a floating ground issue— where a device is using a ground path that wasn't intended. In your case it seems that the SH gauges have found a path of lesser resistance by grounding through the heater slider backlight bulb.
The culprit would be a marginal ground for the SH gauges. Maybe rewire their ground somewhere different and directly to the body with no body paint impeding the connection. Metal to metal.

At least I'd try that

 

[Boom62]

Can't comment on the wiring, but I replaced all my bulbs with LED's and used this one to replace the Climate Control bulb in my FJ62

Amazon product ASIN B00MRCK23E

 

[FJACS]

View attachment 2131316
Is the heater control circled in yellow the bulb for the climate control?

I’m not sure if you are asking about the resistor or not? - The way I read that diagram is that the bulbs are represented by the circle with the filament loop inside it. “Heater Control” has a bulb (the circle) the other item is a resistor for the bulb used in 24volt applications. I think you knew that and were asking about the bulb.

I also think you should have left the stock dimmer in place as many of the other backlit items for the dash (hvac slider, dash buttons, etc) are part of that circuit.

 

[60 toy ota]

I'll take some pictures of the actual wiring in a little bit but the climate control light does ground at the dimmer switch. I know because I have a second light for aux switches that originally tapped off only the positive lead of the climate control light, and the aux switch back light wouldn't dim with the rest of the stock lights. Once I rewired the ground to the negative lead of the climate control light, the dimming worked. If you've removed the dimmer switch, you've inturrupted the ground path for all backlights

 

[tmxmotorsports]

Did you ground the speed hut gauges to metal or a wire?