Test Point 2

Test point 2
Data lead, navigation unit-PCM

Open circuit/short to ground
Short to B+
Signal disturbance

Fault code 21

Open circuit/short to ground
1. Pull off plug II on the display and operator control unit.
2. Pull off plug on the navigation unit.
3. Check lead from navigation unit plug pin 7 to plug II pin 17 for continuity and short to ground.

Short to B+
1. Pull off plug II on the display and operator control unit.
2. Pull off plug on the navigation unit.
3. Check lead from navigation unit plug pin 7 to plug II pin 17 for short to B+.

Signal disturbance
Check lead from navigation unit plug pin 7 to plug II pin 17 for short with other leads.