my cars gauges go crazy when i turn on my lights and i cant even see my
gauges at night.. also when i would have my radio on and id turn on the
lights the radio would turn off and not come back on.. when i put the turn
signals on my car my battery gauge and my rpm gauge go up and down with
the turn signal i dont know whats going on i was told it could be a bad
ground but who knows can someone plz help id appreciate the help thanks
What you have does sound like a bad ground. Here's what's happening. When
you're just running your gauges you have a relatively low resistance to
ground. There is a loose ground bolt somewhere but the minimal amound of
current that the gauges are drawing doesn't significantly affect their
operation. When you turn on the lights you now have to supply a ground for
the gauges as well as all the dash lights, or if you're using the turn
signal, the turn signal indicator light. Suddenly the marginal ground that
was okay when you were using the gauges cannot handle the extra current from
the light bulbs you're trying to power. It's like having a resistor in
between the ground wire and chassis ground that increases it's value when
the current through it goes up. You develop a substantial voltage across
that "resistor" which can cause the problems you're experiencing.
The gauges may actually be effected too. They may be giving an incorrect
reading but since the current isn't radically changing, everything looks
normal.You just don't notice that the voltmeter is pointing at 13.5V when it
should be at 14.2V. What you do notice is the instant change in gauge
readings as soon as you turn on the lights or turn the signal. The gauges
seem to pulse, changing their indicated values, as the turn signal, (or
lights) turn on or off.
This sounds like a bad ground problem. What you need to look for is a ground
wire with an eyelet. There's a bolt through the eyelet that has loosened.
Tightening the bolt with a socket or wrench should fix the problem. You just
need to find the bolt.
Start looking under the dash. Take out the panel, if there is one, under
the steering column and look around the steering column mounting bracket.
Look near the firewall. If you don't find it there, look on the passengers
side. Look under the hood by the firewall, or on the fenders. These are
places that you can typically find the ground. Also, there may be more than
one wire in the eyelet. It may be a junction of 2 or more wires sharing the
same eyelet. Let us know what you find.
Hope this helps,
This problem sounds like a classic:
Just like someone did the valve cover gaskets, and didn't put back on the
two ground straps from the firewall to the valve cover bolts.
Look there first, then look under the dash at the driver's side, there is a
metal bracket that holds in the instrument cluster in the plastic part of
the dashboard, and also a few screws that penetrate the metal bulkhead, that
holds the brake/clutch pedal, if the car is manual transmission. So a loose
dash trim screw may be the culprit.
If you have replaced your stock radio for an aftermarket, make sure that you
didn't short the black wire from the radio plug, it's a long shot, but can
cause the same problems on an unfused install.
my car is a manual transmission and i had put an after market radio on my
car but i took it off because of the problems when i turn on my lights so
um what is the certain screw that i need to tighten or what..
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