Start by locating the three primary connectors on the air intake regulator: power input, sensor feed, and signal output. Pin 1 (typically red) delivers +12V from the ignition-switched circuit–verify.

Begin by locating the 5-pin connector on the electronic air regulator assembly. The standard configuration assigns terminals as follows: Terminal 1 (ignition-switched 12V power), Terminal 2 (ground), Terminal 3.

Start with the main fuse block under the driver-side dash–pin 1 feeds constant 12V to the ignition switch. Trace the red/pink wire through the firewall grommet to the starter.

If the tachometer or speedometer behaves erratically, check the purple/white wire at the instrument connector–this is the primary voltage feed from the ignition switch. A break here often mimics.