Pinpoint Tests

: CHECK THE FORWARD ALERT SWITCH

G240073t2 : CHECK THE FORWARD ALERT SWITCH GROUND
1. Disconnect the forward alert switch electrical connector, IP50.
2. Measure the resistance between IP50, pin 06 (B) and GROUND.

- Is the resistance greater than 5 ohms?

-> Yes
REPAIR the high resistance circuit. TEST the system for normal operation.

-> No

G240073t4 : CHECK THE FORWARD ALERT SWITCH TO ASCCM CIRCUIT FOR HIGH RESISTANCE
1. Disconnect the battery negative terminal.
2. Disconnect the ASCCM electrical connector, EC23.
3. Measure the resistance between IP50, pin 07 (U) and EC23, pin 12 (U).

- Is the resistance greater than 5 ohms?

-> Yes
REPAIR the high resistance circuit. TEST the system for normal operation.

-> No

G240073t5 : CHECK THE FORWARD ALERT SWITCH TO ASCCM CIRCUIT FOR SHORT CIRCUIT TO GROUND
1. Measure the resistance between IP50, pin 07 (U) and GROUND.

- Is the resistance less than 10,000 ohms?

-> Yes
REPAIR the short circuit. TEST the system for normal operation.

-> No

G240073t1 : CHECK THE FORWARD ALERT SWITCH GROUND CIRCUIT FOR SHORT TO B+
1. Measure the voltage between IP50, pin 06 (B) and GROUND.

- Is the voltage greater than 3 volts?

-> Yes
REPAIR the short circuit. This circuit includes the splice IPS 35. TEST the system for normal operation.

-> No
INSTALL a new message center switch. CLEAR the DTC. TEST the system for normal operation. If the DTC is repeated, contact dealer technical support for advice on possible ECM failure.