Making a Cluster Test Bench

[88GreenVN]

I'm making a test bench for the clusters in the Commodores. I want to be able to test the fuel & temp gauges without needing to pull my dash apart in my car.

I have the dash loom and cluster connected to a battery. Put a switch to turn the trip computer lights on.

BUT I can not get the fuel gauge to move. If I put 12 volts to it the gauge jumps instantly.

What am I missing??? - Tan wire to the fuel sender and the other wire to earth. Should work - but no.

Anyone point me in the right direction?

[levymetal]

haha i'm probably not going to be of much help as i don't know how it actually works... but what happens if you put a lower voltage through it, say 3 or 6 volts? i would think that the voltage represents the level of fuel in the tank and how far the needle will move - but i'm probably wrong

[88GreenVN]

I have a sender connected to the loom and to the cluster. May have to get my brother to sus it out.

[Calaber]

Hi Shane

Are you also earthing the instrument cluster when you run the test? Also, in older cars at least, the instruments were protected by some sort of resistor or capacitor which reduced the power to the instruments to around 5 to 6 volts. No idea whether this applies to cars like the
VN etc, though.

[Shearer]

Have you set up a 'dummy' sender?

[stockies]

Does the IGN wire need to be connected as well at the same time as the tan wire for the fuel??
Are both ground wires being used???

[azzfox]

Apply a lower voltage. The fuel level sender acts as kind of like a variable resister. The higher the float the less resistance, so more current can fed through the fuel gauge giving a higher reading and vice versa.

[88GreenVN]

The sender is not doing anything

I'll take some photos of the set up tomorrow - see what I'm up to

[v6lux]

From the diagram in the factory wiring book;

The Combination Meter has a 10 volt regulator inside that supplies constant 10 volts to the Fuel gauge and Temp gauge with ignition ON. The In-tank fuel level sender is a variable resistor that supplies a variable Earth return (from A) to work the gauge. So it works somewhere in the range between 0 and 10 volts.

[fnlow1]

Any updates 88? I wouldn't mind setting up a bench myself

[88GreenVN]

Any updates 88? I wouldn't mind setting up a bench myself

Going to visit my brother on Monday night. Take the loom with me and the sender unit. He's the bright spark when it comes to wires n stuff like that.

I'll update as I get things working.

[VXHBD6]

Let me know how it goes Shane, outcome will be interesting!

[88GreenVN]

The test bench wiring has been sorted out. I can make the fuel gauge move with the sender unit (it failed due to bad connector) The temp gauge will also move if I blip it with 12 v. So now it's tidy up all the wires and mount in the timber holder.

[Dum*P*ster]

Pics? pwease

[fnlow1]

Pics? pwease

+1

10char

[88GreenVN]

Will do in the morning - batteries are on charge right now

The wires look awful at the moment. Going back to the shed to solder and tape the switches in.

[88GreenVN]

Here is a sneak peak at the stage 1 test bench

[Dum*P*ster]

Oooh, this I like.

So, with this setup..You can test all the Gauges ? speedo/temp/rev . aswell?

If so, how exactly do you make the speedo go up and down etc?

Interested in how youve done this.

Top job!

[88GreenVN]

Oooh, this I like.

So, with this setup..You can test all the Gauges ? speedo/temp/rev . aswell?

If so, how exactly do you make the speedo go up and down etc?

Interested in how youve done this.

Top job!

The test bech thing is at stage 1.

Diag mode works.
3/4 of the warning lamps work.
Fuel sender works and reports volts in diag mode 2.
temp gauge moves if I put 12 volts (need to make this a 4 setting switch to go cold to hot)

Things to hook up still:
Main dash lights
Some of the warning lights.
Speedo
Tacho
Temp switch (set to normal running voltage)

So for now I should be able to calibrate VN L3 fuel gauges and test the gauge against the car's sender. If the diag mode shows volts and the gauge fails to move - it's the gauge or cluster. If no voltage in the middle screen it's the sender.

This should also be able to pick lazy gauges - when you fill up and it only shows 7/8's and drops quickly only to take 40 lts at fill up.

[Shearer]

Looks good. Saves putting it the car and out again.

[88GreenVN]

All warning lamps are working as are the cluster globes. Temp and fuel gauge are working off the same sender with a switch to isolate the temp gauge.

So only the tacho and speedo to go.......... (scratches head)

[TVR-190]

i know, wire up an ls1 with an accelerator pedal

[Shearer]

So only the tacho and speedo to go.......... (scratches head)

I have an idea for the speedo.... maybe use a motor from a drill (probably a cheap Chinese one or a good 2nd hand one) and use it to run a speedo sensor from, say a VN auto trans.

I don't think the same would work for a tacho as they use the pulses from a running engine....

[NickVR]

Use a dial to wind up the gauges instead of switches. That way you can test them through out the range. Looks good what you have done so far though.

[88GreenVN]

This thing is almost working 100% (tacho and speedo to go)

Photo's added .