Noob dash issues

[DW73Chevy]

Hello all, this is post #2. I have a ‘73 C10 and it came with some dash issues, surprisingly not lighting, those work great- my issue is that several of my gauges aren’t working. My speedometer (and odometer- my truck permanently only has 813 miles on it ), oil pressure, and temp gauge are not functional. My fuel gauge and my battery voltage work fine. I’m assuming this has something to do with the circuit board since it’s not just one gauge, but can anyone shed some light on this? I have aftermarket oil pressure and voltage gauges, but I’m trying to get the original equipment working as it should.

I’m sorry if this specific issue has been discussed, but I’m still working my way through this forum.

Thanks!

 

[Ricko1966]

Hello all, this is post #2. I have a ‘73 C10 and it came with some dash issues, surprisingly not lighting, those work great- my issue is that several of my gauges aren’t working. My speedometer (and odometer- my truck permanently only has 813 miles on it ), oil pressure, and temp gauge are not functional. My fuel gauge and my battery voltage work fine. I’m assuming this has something to do with the circuit board since it’s not just one gauge, but can anyone shed some light on this? I have aftermarket oil pressure and voltage gauges, but I’m trying to get the original equipment working as it should.

I’m sorry if this specific issue has been discussed, but I’m still working my way through this forum.

Thanks!

If you have aftermarket gauges,I would assume someone disconnected and removed the original senders for the original gauges I'd start by seeing if you have mystery disconnected wires in the engine compartment. What engine ? As for speedometer odometer make sure the cable is connected at the transmission and speedometer,I'd also verify the cable isn't broken. If you can pull the cable out of the housing an inch your cable is broken.

 

[Chevy 88]

Speedometer - use fee phone app for speed (GPS Speedo)-
Oil pressure - low priority, should be addressed asap.
Temp gauge - high priority, should be addressed asap.

For about $20 you can solve all your problems.

Amazon.com

 

[idahovette]

A 73? should have a mechanical oil pressure gauge....that is, a copper line from the engine to the dash gauge....

 

[ali_c20]

Use the search function here. This forum contains tons of truck wisdom. Search for wiring diagrams and there is a lot of information and video material on rebuilding gauge clusters online. Parts like gauges, printed circuits, housings are available at Lmc truck, Classic parts, etc.

 

[75gmck25]

As already mentioned, the oil pressure gauge is mechanical, and it has a hard line running through the firewall to the engine. Sounds like someone left it disconnected.

To start with electrical, first verify that there is a black ground wire running from the cluster plug over to a post on the top of the emergency brake mechanism. If the ground wire is missing you will have multiple panel and light issues.

Temp gauge has to match the temp sensor, and the sensors for early 70’s engine have different resistance profile than later trucks. The original sensors are no longer available from standard parts store, and classic vehicle sources are more expensive. I found a T6T sensor (IIRC) from Autozone is very close to right.

The speedometer cable from Autozone has the right cluster connector, but other sources may have a newer cable with the wrong end. The old cluster has a large clip that holds the end, while some newer clusters use a threaded fitting. The threaded fitting will not clip properly onto your cluster.

Your ammeter gauge will probably never work correctly because it depends on two small fuses under the hood, and several wiring connections. Most mechanics don’t understand that it uses all the wire under the hood as a shunt, so they disconnect or remove the wiring. Just plan to replace it with a voltage gauge. You can find articles online that explain how to do the rewiring, and buy a volt gauge from LMC.