Dash cluster problems

[Jalopy]

So I swapped the cluster out of my 1973 chevy truck with a 1975 cluster and now the left turn signal stays on the only thing different about it is the old one had an
Amp meter and the new one has a volt (the volt meter didn't turn on when the truck was started) I don't know why. I know everyone's answer is oh it's a bad ground but its not the old cluster worked perfectly fine how do I fix this

 

[Vbb199]

Different pinout possibly

 

[idahovette]

My 75 K20, original cluster has an ammeter, not sure when they went to voltmeters???

 

[75gmck25]

If it has a voltmeter it’s not a ‘75 cluster. However, it could have been modified.
The ammeter cluster connects to two wires under the hood to get an amp reading, but it seldom works right with old wiring. It’s also common to have the fuses in those two wires (two barrel fuse holders under the hood) blow.

Do both clusters have a mechanical oil pressure gauge, with a line running through the firewall to the engine?

Did you ground the new cluster to the post on the top of the emergency brake mechanism? Or where did you ground it?

 

[Jalopy]

If it has a voltmeter it’s not a ‘75 cluster. However, it could have been modified.
The ammeter cluster connects to two wires under the hood to get an amp reading, but it seldom works right with old wiring. It’s also common to have the fuses in those two wires (two barrel fuse holders under the hood) blow.

Do both clusters have a mechanical oil pressure gauge, with a line running through the firewall to the engine?

Did you ground the new cluster to the post on the top of the emergency brake mechanism? Or where did you ground it?

I didn't change anything I unplugged the old on put my old gauges in the the new one and plugged the new one in I didn't disconnect the ground

 

[Rickf]

You might need to swap the printed circuit also.

 

[Jalopy]

You might need to swap the printed circuit also.

We tried but the print is different

 

[Rickf]

Check this thread....

Instrument cluster upgrade 1974 C10

Hope I am posting this in the right place. I have a 1974 Custom 10 (Inline 6), and from the factory, it has: warning lights, speedometer and fuel. That's it. I bought a full gauge cluster off eBay from a 1973 V-8 truck. I have since been rebuilding it and preparing it for my truck. Here is...

www.gmsquarebody.com

 

[75gmck25]

I don’t want to beat you up about it, but you need to be more clear about what you did. Apparently you left your old cluster in place and just swapped the gauges from the donor cluster.

Therefore I’m still confused about how both of these clusters could have a voltmeter, which was not used in a 73-75 cluster. Has someone been in there before and messed with the gauges, circuit board, or other wiring ? Maybe that is the real problem.

 

[Vbb199]

PO's hacking wiring up is always the problem with these trucks, seldom do I find one that hasn't been mutilated, which is why I cherish my suburban being as My dad was the first owner.

That said, it sounds like maybe YOUR previous owner maybe messed with it a little, one would have to ask "why" a gauge was tampered with in a rare 1973 chevrolet truck.

The 73 parts and pieces are almost non existent in aftermarket, especially the dash bezel and cluster.

 

[Jalopy]

I don’t want to beat you up about it, but you need to be more clear about what you did. Apparently you left your old cluster in place and just swapped the gauges from the donor cluster.

Therefore I’m still confused about how both of these clusters could have a voltmeter, which was not used in a 73-75 cluster. Has someone been in there before and messed with the gauges, circuit board, or other wiring ? Maybe that is the real problem.

Sorry I'm not that good at explaining things and honestly i dont know what year the new cluster is a guy with a 75 gave it to me but I will go on a step by step so we removed the 73 cluster out of the truck due to it being broken probably by the previous owner. We then removed all the gauges out of the new cluster and the 73 cluster. Then we put my 73 gauges in the new cluster but we used the volt meter out of the new cluster because the printed circuit was designed for it. Next we installed the new cluster with my 73 gauges in the truck, everything worked but the volt meter and when the headlights were turned on the left blinker light stayed on.

 

[Terry Wilkerson]

Measuring amps and volts are different. Amps are measured with the meter in the circuit. Which means it is like taking the hot wire from a motor or a alternator and cutting it, connecting one end of the wire from the alternator to the one post of the amp meter and the other end of the wire to the other post. Then it goes to where ever it is needed to supply power. Measuring volts is putting one lead of a volt meter on a hot wire and the other lead of the volt meter to a ground.
I suspect this difference is the reason your volt meter didn't work. If you still have the amp meter try putting it in and see if it works. This probably clear as mud but there is a difference in the way amp and volts are measured.

 

[Jalopy]

Measuring amps and volts are different. Amps are measured with the meter in the circuit. Which means it is like taking the hot wire from a motor or a alternator and cutting it, connecting one end of the wire from the alternator to the one post of the amp meter and the other end of the wire to the other post. Then it goes to where ever it is needed to supply power. Measuring volts is putting one lead of a volt meter on a hot wire and the other lead of the volt meter to a ground.
I suspect this difference is the reason your volt meter didn't work. If you still have the amp meter try putting it in and see if it works. This probably clear as mud but there is a difference in the way amp and volts

We got the volt meter working but the left blinker is still on

 

[Jalopy]

The left blinker stays on when the lights are turned on it doesn't "blink" it just is on

 

[Turbo4whl]

The left blinker stays on when the lights are turned on it doesn't "blink" it just is on

Check the left front park/turn bulb and socket for a bad ground or bad bulb.