Datsun 1200 comes with a full temperature gauge in the dash, controlled electrically by the Thermal Transmitter (sender) that is screwed into the cylinder head.
Also see: Instruments and Controls#Water Temperature Gauge
Troubleshooting
- If both fuel and temperature gauges do not work at all, the fuse is likely burnt out. Inspect the fuse. If the fuse is good, the instrument panel voltage regulator may be bad
- If both fuel gauge and temperature gauge read incorrectly (high or low) or fluctuate, the problem is likely the shared instrument panel voltage regulator. But first check the wiring connections. They may be loose or corroded.
- If gauge reads MAX hot with ignition OFF, gauge is defective.
- If gauge reads MAX hot with ignition ON, but cold with ignition OFF, transmitter is bad
- Ground sensor wire at engine. If gauge fluctuates, gauge is bad
Accuracy Test
- Buy a 116-ohm resistor at Radio Shack or other electronics store.
- At the engine, locate the thermal transmitter:
- Pull the wire off the transmitter and put a 116-ohm resistor from the wire to earth/ground
- Turn IGN switch to "ON". Gauge should read 50C/122F, or between C and H ranges (in middle range)
Clean the connections.