How to Wire an Oil Pressure Gauge

What You'll Need
Oil pressure gauge
18 gauge wiring

To wire an oil pressure gauge, make sure to get a copy of the wiring diagram for the specific brand and model of the device. The manual usually comes with the purchase, but the manual can also be downloaded from the manufacturer’s website. Here are the instructions on how to wire an oil pressure gauge.

Step 1 – Preparation

Purchase an oil pressure gauge that is compatible with the car. To install the device into the car, make sure to open the car’s hood and locate the oil pressure gauge. The gauge should be found near the oil filter of the engine. Make certain that all wiring connections are properly detached before pulling the gauge out of the car. When the old gauge is removed, insert the new oil gauge into the slot and begin with the wiring process.

Step 2 – Connect the Red Wire

First of all, detach the negative battery cable. Now connect the red wire from the oil pressure gauge to a positive 12 volt ignition source. It can also be connected to any positive 12 volt source that turns off or on in connection to the vehicle’s ignition switch. If the source does not have a fuse, make sure to install a fuse in the wiring. An additional circuit accessory can be purchased and added to the fuse panel for this purpose.

Step 3 – Connect the Yellow Wire

Connect the yellow wire to the un-switched positive 12 volt constant. This can be done indirectly through the fuse panel of the vehicle or directly to the battery. If the source does not have a fuse, make sure to install a fuse inline.

Step 4 – Connect the White and Green Wire

Locate the pressure sensor and locate the white wire and the G Post. Connect the white wire on the sensor to the white wire on the gauge. Afterwards, connect the green wire on the oil pressure gauge to the sensor’s G post.

Step 5 – Connect the Black Wire

When all other connections have been established, take the black wire from the oil pressure gauge and connect it to the black wire on the pressure sensor. Route the connection to an unpainted ground connection. The wire can also be routed directly to the vehicle battery’s negative side.

Step 6 – Re-attach the Negative Battery Cable

Re-attach the cable to complete the wiring process. In order to avoid damage to the gauge or cause it to malfunction, take note not to connect it to a dimmer. A dimmer switch unit will definitely interfere with the functions of the oil pressure gauge and thus display incorrect readings.

Step 7 – Test

Double check if all corrections are in line with the wiring diagram in the service manual. Inspect for loose connections and wiring errors as well. Turn on the car engine to test the gauge.