-
Senior Member
HELP!! Speedhut inverter/dimmer
Has anyone had one of these go bad? I am wiring up my dash with the RF harness and can get the pointers to work with the red/blk/white ribbon but can't get the backlights of the gauges to come on with the white/blk wires no matter what I do. Wiring is not my forte so if there is a way to test it I'll be happy to try that. I have tried direct blk/white to a 12V jumper. I did buy the gauges used but was assured they worked. Any help would be great!!
Higgy
Last edited by Higgybulin; 12-10-2019 at 11:17 AM.
MK4 #11012 picked up 04/16/24
MK4 #10616 picked up 4/10/23
302w, 4 link, 17's, dual roll bar SOLD
MK4 #9759 picked up on 4/3/19
351C, 3 link, 17's, dual roll bars SOLD
-
Senior Member
Yes, the inverter has been known to be defective and/or fail. The version of the gauges that uses the inverter (there's apparently a newer version that doesn't...) won't light the AC powered backlighting without it. So direct wiring with 12V DC won't do anything. Ideas? Make sure the knob on the included little potentiometer is turned up. Make sure the knob on your headlight switch is twisted all the way clockwise. The dash gauge lighting circuit goes through the dimmer function on the headlight switch. Sometimes guys have that knob turned down to where the gauge lighting doesn't have enough voltage to light. The inverter needs the proper DC voltage in. Start there for the obvious possibilities. Next steps would be to start probing with a VOM. If you have to call Speedhut, I've found their customer service is very good.
Build 1: Mk3 Roadster #5125. Sold 11/08/2014.
Build 2: Mk4 Roadster #7750. Sold 04/10/2017.
Build Thread
Build 3: Mk4 Roadster 20th Anniversary #8674. Sold 09/07/2020.
Build Thread and
Video.
Build 4: Gen 3 Type 65 Coupe #59. Gen 3 Coyote. Legal 03/04/2020.
Build Thread and
Video
Build 5: 35 Hot Rod Truck #138. LS3 and 4L65E auto. Rcvd 01/05/2021. Legal 04/20/2023.
Build Thread. Sold 11/9/2023.
-
Senior Member
Originally Posted by
edwardb
Yes, the inverter has been known to be defective and/or fail. The version of the gauges that uses the inverter (there's apparently a newer version that doesn't...) won't light the AC powered backlighting without it. So direct wiring with 12V DC won't do anything. Ideas? Make sure the knob on the included little potentiometer is turned up. Make sure the knob on your headlight switch is twisted all the way clockwise. The dash gauge lighting circuit goes through the dimmer function on the headlight switch. Sometimes guys have that knob turned down to where the gauge lighting doesn't have enough voltage to light. The inverter needs the proper DC voltage in. Start there for the obvious possibilities. Next steps would be to start probing with a VOM. If you have to call Speedhut, I've found their customer service is very good.
Paul, does my headlight switch need to be in the mix. I put the 12V right to the blk/wht wires on the inverter, and played with the dimmer switch
MK4 #11012 picked up 04/16/24
MK4 #10616 picked up 4/10/23
302w, 4 link, 17's, dual roll bar SOLD
MK4 #9759 picked up on 4/3/19
351C, 3 link, 17's, dual roll bars SOLD
-
Senior Member
I had one go bad. The replacement was a newer version.
-
Senior Member
Originally Posted by
HiggyMK4#9579
Paul, does my headlight switch need to be in the mix. I put the 12V right to the blk/wht wires on the inverter, and played with the dimmer switch
My response was assuming you had the dash wired. My bad. No. The headlight switch doesn't add anything if you're applying power directly. You can bench test the gauges. I assume you have all the gauges wired together with the supplied daisy chain cables. The black and white wires for the inverter should power the backlighting. Turning the pre-wired potentiometer should adjust the level. The 3-wire cable does the rest. Red = gauge power, white = pointer lighting, black = ground.
Build 1: Mk3 Roadster #5125. Sold 11/08/2014.
Build 2: Mk4 Roadster #7750. Sold 04/10/2017.
Build Thread
Build 3: Mk4 Roadster 20th Anniversary #8674. Sold 09/07/2020.
Build Thread and
Video.
Build 4: Gen 3 Type 65 Coupe #59. Gen 3 Coyote. Legal 03/04/2020.
Build Thread and
Video
Build 5: 35 Hot Rod Truck #138. LS3 and 4L65E auto. Rcvd 01/05/2021. Legal 04/20/2023.
Build Thread. Sold 11/9/2023.
-
Post Thanks / Like - 0 Thanks, 1 Likes
-
Senior Member
-
Post Thanks / Like - 0 Thanks, 1 Likes
-
Just a tip here. First car we used the Speedhut gauges in we tried the gauge lights in the well lit shop and could not tell if they were working. Turned down/off all of the shop lights and what do you know, they worked.
-
Senior Member
Originally Posted by
i.e.427
Just a tip here. First car we used the Speedhut gauges in we tried the gauge lights in the well lit shop and could not tell if they were working. Turned down/off all of the shop lights and what do you know, they worked.
I definitely had the shop lights off, I think it's toast. Good news, as many have said before Speedhut has pretty good customer service! A new one is on the way.
MK4 #11012 picked up 04/16/24
MK4 #10616 picked up 4/10/23
302w, 4 link, 17's, dual roll bar SOLD
MK4 #9759 picked up on 4/3/19
351C, 3 link, 17's, dual roll bars SOLD