Circuit/System Testing

WARNING: This page is about a different car, the 2010 Cadillac SRX. However, it is still accessible from the selected car via links, so may be relevant.

Ignition OFF, disconnect the harness connector at the inside rearview mirror.
Test for less than 15 Ω between the mirror ground circuit terminal 5 and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
Ignition ON, test for less than 1 V between the keypad signal circuit terminal 3 and ground.
- If greater than the specified range, test the keypad signal circuit for a short to voltage. If the circuit tests normal, replace the K73 telematics communication interface control module.
Ignition OFF, test for 500k-850k Ω between the keypad signal circuit terminal 3 and ground.
- If less than the specified range, test the keypad signal circuit for a short to ground. If the circuit tests normal, replace the K73 telematics communication interface control module.
- If greater than the specified range, test the keypad signal circuit for an open/high resistance. If the circuit tests normal, replace the K73 telematics communication interface control module.
Ignition ON, test for 9.5-10.5 V between the keypad supply voltage circuit terminal 4 and ground.
- If less than the specified range, test the supply voltage circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the K73 telematics communication interface control module.
- If greater than the specified range, test the supply voltage circuit for a short to voltage. If the circuit tests normal, replace the K73 telematics communication interface control module.
If all circuits test normal, test or replace the button assembly.