[DeTomaso] headlights vs temp guage

[Scott Couchman]

Bill, you sent me a photo of the back of the water temp gauge when you repaired my
gauge. It shows a daisy chained pair of black wires for ground, a pair of daisy chained pink
wires from fuse 12 for power, a red/black sensing wire to the sender, and yellow/black wire
for power to the lamp.

On the photo you indicate that the sensing wire connects to the temp sensor on some cars
through a resistor. Is that to compensate for the issue with the light bulb grounding and
does that solve the problem too?

Given the design of the light bulb socket, I'm guessing supplying a separate ground for the
light bulb circuit won't be easy. Besides dedicated gauge grounds, would replacing the
incandescent bulbs with LEDs also solve the problem. The lower current draw of the LEDs
would make the circuit less sensitive to the grounding (not sure if LED replacements are
available).