Unfused Components

Determine Unfused Components With Increased Quiescent Current Consumption





References (WH), Commercially available tools.

1 Determine unfused components, these are e.g.:
Consumers of the exhaust gas recirculation (EGR) system.
Consumers of the airbag (AB) system.
Consumers of the knock sensor system (KSS).
Consumers of the electronic ignition (HFM-SFI/PEC) system.
Anti-theft systems, e.g. immobilizer.
Consumers of the idle speed control (ISC) system and alternator, starter, ignition switch.

See "Electric wiring diagrams, models 170, 202, 210". Observe after-running time for electronic components: Models 202, 210 approx. 4 min., model 170 approx. 10 min.

2 Read off total quiescent current on multimeter connected to battery and note value.
3 Separate coupling or connection at the likely quiescent current consumer and tie back, if necessary, to prevent contact.


NOTE: The quiescent current consumption may also rise as a result of the radio by about 0.240 A (240 mA). The increased quiescent current consumption can be eliminated by switching the radio on and off.


4 Read off total quiescent current on multimeter and note.

If the decrease in the quiescent current is <= 0.02 A (20 mA) or <= 0.035 A (35 mA), for immobilizer control module:
Component is in order.

5 Plug in coupling or connection again to the component.
6 Repeat test as described with all the possible quiescent current consumers.

If the decrease in the quiescent current is > 0.02 A (20 mA) or > 0.035 A (35 mA), for immobilizer control module:
Replace component.

Once again test quiescent current as a check.