7 replies to this topic

[Iain L]

Im converting to a centre speedo, so have the oil pressure gauge, speedo and the water temp gauge. Got them all off ebay, and the temp gauge was working fine, but when ive come to fix it all in place it now doesnt work.

Checked all wiring and seems to still be ok, ive even run a separate wire direct from the temp transmitter to the gauge still nothing.

So would it just be the gauge has gone knackered? Does look tired. Or could it be the transmitter or the thermostat?

I have tried putting my 12v circuit tester onto the end of the transmitter and that doesnt give a read out. Should it?

Thanks Iain

[Iain L]

Im converting to a centre speedo, so have the oil pressure gauge, speedo and the water temp gauge. Got them all off ebay, and the temp gauge was working fine, but when ive come to fix it all in place it now doesnt work.

Checked all wiring and seems to still be ok, ive even run a separate wire direct from the temp transmitter to the gauge still nothing.

So would it just be the gauge has gone knackered? Does look tired. Or could it be the transmitter or the thermostat?

I have tried putting my 12v circuit tester onto the end of the transmitter and that doesnt give a read out. Should it?

Thanks Iain

Anybody?

[Bungle]

disconnect the wire out of the back of the gauge that goes to the sender in the head

now earth this terminal on the gauge

what happens ?

[Iain L]

disconnect the wire out of the back of the gauge that goes to the sender in the head

now earth this terminal on the gauge

what happens ?

Hi, thanks for reply, nothing happens when i do that.

[Bungle]

is there 12v power between the other 2 terminals ?

[Iain L]

is there 12v power between the other 2 terminals ?

Nope, theres no power anywhere. Even if i put my tester dircet onto temp transmitter i get nothing.

[dklawson]

Since you have purchased a center speedo and related gauges, do you know if this a Mk1 gauge cluster or is it Mk2 (or later)? You said that everything worked until you installed it. How do you know? Did you test it and if so... how?

On the assumption that it is a Mk2 or later speedo cluster, start with the basics. On the back, top of the speedometer should be a small rectangular metal box perhaps the size of the end of your thumb. That is the voltage stabilizer. It must be mounted securely to a non-rusty surface to make an earth connection. There should be dark green wires connected to the stabilizer's "B" terminal. Switched 12V power enters the stabilizer on that "B" terminal. There should be two light green wires connected to the stabilizer's "I" terminal. Each one should go to one of the gauges (fuel or temperature). There should be a green/blue wire on the other terminal of the temperature gauge. There should be a green/black wire on the other terminal of the fuel gauge.

Here is what happens:
12V Power goes into the stabilizer on it's "B" terminal.
10V Power exits OUT of the stabilizer on its "I" terminal.
10V is supplied to the gauges via the light green wires.
Power passes through the resistance elements inside the fuel and temperature gauges.
Power exits the gauges through the green/black and green/blue wires and continues to the sending units.
The sending units are variable resistors connected to earth. They "throttle" the current flowing to earth which in turn alters the gauge reading.

So, if you disconnect the sending unit wire and measure the "voltage" between the sending unit and earth... you will not find any voltage. The sending units are not transmitters, they are resistive elements to earth.

You said there is no power on the temperature gauge. Is the fuel gauge performing correctly? Did you wire up the voltage stabilizer as I mentioned above?

[Iain L]

Since you have purchased a center speedo and related gauges, do you know if this a Mk1 gauge cluster or is it Mk2 (or later)? You said that everything worked until you installed it. How do you know? Did you test it and if so... how?

On the assumption that it is a Mk2 or later speedo cluster, start with the basics. On the back, top of the speedometer should be a small rectangular metal box perhaps the size of the end of your thumb. That is the voltage stabilizer. It must be mounted securely to a non-rusty surface to make an earth connection. There should be dark green wires connected to the stabilizer's "B" terminal. Switched 12V power enters the stabilizer on that "B" terminal. There should be two light green wires connected to the stabilizer's "I" terminal. Each one should go to one of the gauges (fuel or temperature). There should be a green/blue wire on the other terminal of the temperature gauge. There should be a green/black wire on the other terminal of the fuel gauge.

Here is what happens:
12V Power goes into the stabilizer on it's "B" terminal.
10V Power exits OUT of the stabilizer on its "I" terminal.
10V is supplied to the gauges via the light green wires.
Power passes through the resistance elements inside the fuel and temperature gauges.
Power exits the gauges through the green/black and green/blue wires and continues to the sending units.
The sending units are variable resistors connected to earth. They "throttle" the current flowing to earth which in turn alters the gauge reading.

So, if you disconnect the sending unit wire and measure the "voltage" between the sending unit and earth... you will not find any voltage. The sending units are not transmitters, they are resistive elements to earth.

You said there is no power on the temperature gauge. Is the fuel gauge performing correctly? Did you wire up the voltage stabilizer as I mentioned above?

Hi, only just got round having another look at the gauge, and connected it up to the voltage stableiser and now it works!
Thanks very much mate, big help