Pinpoint Tests
PINPOINT TEST A: THE MESSAGE CENTER SWITCH DOES NOT OPERATE CORRECTLYNormal Operation
The message center functionality is controlled through the message center switch, which is hardwired to the instrument cluster (IC) through input circuit CMC29 (GN/VT) and return circuit VMC29 (YE). There are 3 message center switch buttons, with each button operating a switch that uses different resistance values. The instrument cluster (IC) sends out a reference voltage to the message center switch on the input circuit and monitors the voltage drop when a message center switch button is pressed. The voltage drop will vary depending upon the resistance of each button, providing a specific indication to the instrument cluster (IC) which switch is pressed.
- DTC B1205 (EIC Switch-1 Assembly Circuit Failure) - sets in continuous memory when the instrument cluster (IC) detects any message center switch stuck for greater than 2 minutes and on-demand when the instrument cluster (IC) detects any message center button stuck during the self-test.
- DTC B1206 (EIC Switch-1 Assembly Circuit Open) - is a continuous and on-demand DTC that sets when the instrument cluster (IC) detects an open on the message center switch input, circuit CMC29 (GN/VT).
- DTC B1208 (EIC Switch-1 Assembly Circuit Short to Ground) - is a continuous and on-demand DTC that sets when the instrument cluster (IC) detects a short to ground on the message center switch input, circuit CMC29 (GN/VT).
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Message center switch
- Instrument cluster (IC)
A1:
A2-A4:
A4-A6:
A6-A8:
