Boost gauge light question

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Dhos1

Self-tuning wanna-be

Joined

Apr 14, 2012

• May 9, 2020

• #1

I’m swapping out to Autometer procomp boost gauge and for some reason the bulb holder does not illuminate. The old gauge I replaced had 2 blade terminals a 12volt and a ground. The procomp I am installing doesn’t have any terminals. It has a standard hole that the bulb holder terminal fits in. Bottom line, I’m sure the bulb terminal is good because it was used with a previous gauge. See pics below. Does it have something to do with the new one not having a terminal blade for a ground??

 

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Dhos1

Self-tuning wanna-be

Joined

Apr 14, 2012

• May 9, 2020

• #2

Here’s what the back of the new one looks like

 

salvageV6

Daily Driver

Joined

May 25, 2001

• May 9, 2020

• #3

You forgot a detailed pic. of the bulb holder.

Usually the snap in or twist in holders use the metal frame of the gauge as ground. Try grounding the metal on the back of the gauge.

 

D

Dhos1

Self-tuning wanna-be

Joined

Apr 14, 2012

• May 9, 2020

• #4

Are you saying ground the metal threaded rods ? If that’s the case does only the black power wire get connected and this white wire not get used?

 

1986 Buick GX1

GX1 #001 [The One and Only]

Joined

Apr 24, 2015

• May 9, 2020

• #5

Are there 2 wires on the bulb holder?, the part that holds the bulb and twists into the gauge.

 

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Fat Nat

Well-Known Member

Joined

May 25, 2001

• May 9, 2020

• #6

bulb holder should have 2 terms just like the old gauge slip them on and go. Some of the early gauges had a black and white wire and the real old ones had a single black wire

 

D

Dhos1

Self-tuning wanna-be

Joined

Apr 14, 2012

• May 10, 2020

• #7

1986 Buick GX1 said:

Are there 2 wires on the bulb holder?, the part that holds the bulb and twists into the gauge.

Click to expand...

Yes, a black wire and a white wire

 

F

Fat Nat

Well-Known Member

Joined

May 25, 2001

• May 10, 2020

• #8

Dhos1 said:

Yes, a black wire and a white wire

Click to expand...

Black to a ground usually the bolt that holds the secures the dash The power wire should come out of fuse box marked
Lps

 

1986 Buick GX1

GX1 #001 [The One and Only]

Joined

Apr 24, 2015

• May 10, 2020

• #9

Dhos1 said:

Yes, a black wire and a white wire

Click to expand...

If it’s a new gauge with an LED light, it may be polarity sensitive. You may need to try swapping the wires to see if that works, or try turning the LED bulb around if it’s removable.
If it’s an incandescent bulb you can check the continuity of the bulb itself and the bulb/ holder as an assembly.

You’ve probably tried all this, just a thought.