Does anybody know if there is an unused wire in the wiring loom between the engine bay mounted relay fuse box and dashboard connectors in a low BCM equipped VR Commodore. Trying to hook up an electric oil pressure guage and hoping there is a spare wire in the loom to tap into to.
Heres how to install an oil pressure gauge in a VN, it might help you out, it might not: http://forums.justcommodores.com.au.../59661-vn-how-install-oil-pressure-gauge.html
The sender in the link above converts the oil pressure signal at the motor to an electric signal which would solve the problem one way. After reading the Holden Service Manual, there is a Oil Pressure Switch right where the Oil Filter is. if you're looking at the Oil Filter straight on where it's pointing to the bottom right, the switch should be right in front of you. it sits 90 degrees to the oil filter and points to the front of the car. 1. Check engine oil level and add oil as required. 2. Ensure that engine is at operating temperature. 3. Pull out retaining tang on engine harness connector at oil pressure sender unit and pull connector from sender unit. 4. Loosen and remove oil pressure sender unit from oil filter adaptor. 5. Install a suitable oil pressure gauge assembly into oil filter adaptor oil pressure sender unit hole. 6. Start engine and check oil pressure reading with engine running under no load. After following the wiring diagrams, there's no oil pressure wire going to the PCM or the BCM. It's wired straight to the Oil Pressure Warning Lamp on the dash of the car. There's another circuit that goes to the coil and the fuel pump relay, but I'm not 100% sure about this. If it's the Oil Pressure Warning Lamp then this will be pin #8 on instrument connector #1. It's possible it'll be able to work out the actual reading from this wire as the trip computer is able to work out exact L's in the tank from the fuel wire from the level of resistance. From memory in the older cars the temp light used to work off the same wire that the temp gauge worked off, but only lit up when it reached a certain level of resistance. Let us know what you find! The manual also says don't ever earth out these gauges for testing. There's specific measures for testing the gauges and outright earthing them can make them go faulty. I suggest getting one of these manuals so you can follow these circuits Plus it shows all sorts of other sensors you can tap into for various things.
