For 1990-2009 cars

Eight steering wheel control switches are used in order to control the audio and HVAC functions. The steering wheel controls are configured as a resistor network. Each switch has a unique resistance value.

When the ignition switch is in the RUN or ACCESSORY position, ignition positive voltage is provided to the steering wheel controls from the IP fuse block radio fuse through the steering column fuse holder switch fuse (located at the base of the steering column) and the inflatable restraint steering wheel module coil on CKT 43 (YEL). Pressing a steering wheel control switch causes voltage to pass through the resistor(s) to the radio on CKT 1011 (LT GRN). The radio processes the value received and commands the proper radio function. The radio sends a serial data message by the E and C serial data line on CKT 835 (DK GRN) to the HVAC system in order to control the proper function.

### Steering Wheel Controls Resistance Table

The resistance values provided are measured from pins A to C of the steering wheel controls with the steering wheel controls disconnected. The actual resistance measured should be within 10 percent of the value listed.

Switch | Resistance
--- | ---
SW 1 | 1270 ohms
SW 2 | 1564 ohms
SW 3 | 1912 ohms
SW 4 | 2387 ohms
SW 5 | 3102 ohms
SW 6 | 4282 ohms
SW 7 | 6652 ohms
SW 8 | 13632 ohms