why do my guages go crazy when I turn the reostat on my headlight switch?

Asked by Sep 01, 2014 at 10:20 AM about the 1965 Pontiac GTO

Question type: Maintenance & Repair

When I adjust the resorts on my headlight switch my temp, oil, and gas gauges pin until
I completely turn resorts all the way counter clockwise. ANY IDEAS?

3 Answers

35,005

Did it get wet? Or..........You haven't been messing around with anything electrical lately have you?

Best Answer Mark helpful
69,465

When you say "pinned" do you mean the gauges go to Full, Hot, etc.? Or the other way? When I first bought my '70 Catalina the gauges would all go to Empty, Cold, etc. when I switched on the headlights. The turn signal indicators and high beam indicator would light dimly as well. The problem was a bad ground at the instrument cluster. The previous owner had installed an aftermarket radio and forgot to hook one of the ground straps back up to the instrument cluster. HTH. -Jim

Best Answer Mark helpful
4,745

The rheostat is probably bridged with metal worn off over time. Then that happens, there is a surge of current draw at different areas of the rheostat. You can get an authentic aftermarket replacement switch for that car from Ames Performance, OPG, or Performance Years. I would agree with JS08016 also - check the ground to the instrument cluster as well as the ground connection at the headlight switch. Any stray voltage coming off the rheostat seems to be finding it's way to ground via the gauges.

1 of 1 people found this helpful.

Your Answer

GTO

Looking for a Used GTO in your area?

CarGurus has 459 nationwide GTO listings starting at $5,995.

ZIP:

Pontiac GTO Experts

  • #1
    Rucko
    Reputation
    780
  • #2
    Norm Davis
    Reputation
    340
  • #3
    F_O_R
    Reputation
    170
View All

Related Models For Sale

Used Ford Mustang
745 Great Deals out of 42,276 listings starting at $1,300
Used Chevrolet Corvette
234 Great Deals out of 22,105 listings starting at $2,500
Used Dodge Charger
423 Great Deals out of 27,560 listings starting at $1,650
Used Chevrolet Impala
569 Great Deals out of 34,584 listings starting at $1,250
Used Pontiac Grand Prix
37 Great Deals out of 2,736 listings starting at $1,200

Used Cars For Sale

2006 Pontiac GTO For Sale
4 Great Deals out of 113 listings starting at $9,200
2005 Pontiac GTO For Sale
64 listings starting at $9,995
2004 Pontiac GTO For Sale
5 Great Deals out of 121 listings starting at $5,995

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.