Test Point 3

Test Point 3

Speed
- Ignition on
- Engine off

PST2 display 0 rpm
- Engine idling PST2 display.
Tester display approximately equal to engine speed in rpm

Troubleshooting:
- Switch off ignition
- Pull off plug II on the instrument cluster
- Engine idling
- Measure the voltage between instrument cluster plug II, pin 15 and ground (AC range) Voltmeter display: > 1 V
- Disconnect plug on DME control module (ME 5.2) or
- Disconnect plug IV on DME control module (ME 7.2)
- Switch ignition on
- Measure the voltage between instrument cluster plug II, pin 15 and ground Voltmeter display: 0 V
- Ohmmeter on instrument cluster plug II pin 15 and plug on DME control module (ME 5.2) pin 80 or ME 7.2 plug IV pin 17 Ohmmeter display: < 5 Ohms.
- See also Drive Links chapter, "Tachometer"