Test Point 6 - Idle Speed Control
TEST POINT 6: - Idle speed control (V) - Fault code 1_22Possible Causes, Elimination, Remarks
Drive link activation menu
If no pulse is audible, check power supply.
Connect the voltmeter to terminal 2 and ground of the disconnected plug of the idle speed control using test leads. Switch ignition on.
Display: Battery voltage
If no display: Check power supply in accordance with wiring diagram.
Control signal test
Using the system tester 9288, it is possible to read the pulse duty factor in percent directly in the "Actual value" menu.
Function test:
Switch on loads during idle operation. The pulse duty factor must change, while the idling speed remains constant. If not:
Connect a 2-pin DME test lead (Bosch No. 1 684 463 093) between the speed control and plug.
Connect and adjust engine tester in accordance with manufacturer's instructions.
Ensure that the lead connections do not have any ground contact with the vehicle. (Danger of short-circuit)
This display must be visible when the engine is running: Frequency approx. 100 Hz.
If no audible pulse exists in spite of the voltage and signal being present, replace the idle speed control.