completely off the wall questions.

ASSISTANCE Electrical & Entertainment Systems
1

I removed my tachometer out of my factory cluster in to install my tunerview, in doing so the temp gauge quit working as did the fuel gauge. fuel gauge pegs out at Full and temp gauge pegs out at HOT immediately as you turn the car on. if I unplug the temp sending unit wire the temp gauge goes back down to cold…

I know pretty much that all the sensors on the circuitry thing share the same common power and ground, did removing the tach disrupt this? how do i fix it if it did?

I’m more worried about making the fuel gauge work.

2

Yes, the tach, fuel gauge and engine coolant temperature gauge share a common ground and power, but they are parallel connections, so removing one of them should have no effect on the other two, I would recheck the grounds to the fuel and temp gauge.94

3

could I just reground them? Say to the chassis?

I did take the fuel gauge out and try to run wires off the dash harness to the gauge… it would either go straight to full or straight to empty… no in between.

Everything else on the cluster works just fine… the only thing I did was remove the tach.

4

Have you checked to see if the gas and temp gauges are getting a ground? 94

5

Like I said, I used a test light and put them to the ignition power screw and the ground screw and it lit up, so I assume yes they are.

6

If test light lights up when the probe is put on the “ignition power screw and the ground screw” then there is no ground, a ground that is not grounded will test as 12V+, it is the power on the other side of the load. 94

7

How would you recommend grounding it? Running two ground wires from the ground screws to the chassis?

8

I tried running ground and power wires from their screws in the back of the gauges and it didnt work.

I really think the tach has something to do with the circuitry.

9

As I said the power and grounds to the 3 gauges are parallel connections, removing one should have no effect on the others.

Have you metered the black ground lead at the plug for the cluster?

The 12V+ is common, [parallel] to the gauges and the idiot lights, if the idiot lights work, [oil, brake, low fuel, ABS and CEL] then power is not the problem, leaving only the constant ground or “signal” leads, [grounds through resistance.

Meter the yellow/white lead at the plug, should read someplace between 2-5 ohms, [full tank] 25-39 ohms, [half tank] and 105-110 ohms, [empty tank] 94

10

Nah, I didnt check the ground lead (B7 in the 12 pin connector). I’m fairly sure it’s working however. I’m pulling power from B7 and B8 for my oil pressure gauge power/ground.