GM Service Manual Online
For 1990-2009 cars only

The instrument cluster has these power feeds:

    • B+ (circuit 640)
    • Ignition 0 (circuit 1500)
    • Ignition 1 (circuit 39)
    • Crank signal (circuit 806)

The instrument cluster has these ground feeds:

    • Circuit 1550
    • Circuit 1750

Circuit 32 is a signal feed for the dimming control of the VF displays, which is controlled by the headlamp switch.

On vehicles equipped with the Driver Information Display (DID), circuit 893 provides the mode switch signal input, circuit 1816 provides the reset switch signal input, and circuit 811 provides the English/Metric mode switch signal input.

Circuit 1414 and circuit 1415 provide feeds for the control of the turn signal lamp indicators, which is controlled by the exterior lights system.

Circuit 8 is a power feed for the illumination lamps of the gauges, which is controlled by the headlamp switch.

Circuit 1200 provides a power feed for the high beam indicator.

Circuit 1036 is the serial data line, which provides class 2 communications. This line allows the instrument cluster to send/receive data from other vehicle systems.

Circuit 419 is a power feed for the SERVICE ENGINE SOON indicator lamp, which is controlled by the Powertrain Control Module (PCM).

Circuit 99 provides a ground feed for the control of the LOW WASH indicator lamp, which is controlled by the windshield washer solvent level switch.

Circuit 209 provides a ground feed for the control of the brake indicator, which is controlled by the brake fluid level switch. Note that brake indicator is also controlled by other modules via the class 2 serial data line.