Test Point 22-27 - Injector valves

TEST POINT 22 - 27 - Injector valves (V/Ohms)
Fault code 1_51, 1_52, 1_53, 1_54, 1_55, 1_56

Possible Causes, Elimination, Remarks
Using the System Tester 9288, the injector valves may be checked directly in the Drive links menu item or the Actuator active menu item.

Selective injection allows each injector valve to be actuated individually. In case of the Drive links test point, a rather weak switching noise of the injector valves is audible.

In case of the Actuator active menu item, each individual injector valve may be isolated with the engine running.

Power supply




Disconnect valve plug, connect voltmeter to the injector valve plug terminal - refer to drawing - and ground (engine).
Ignition on.

Display: Battery voltage
If no battery voltage is displayed, check according to wiring diagram.

Checking coil resistance of injector valves
Disconnect valve plug. Check coil resistance at injector valve terminal contacts with an ohmmeter.

Test value: approx. 16 Ohms

Injection output stage
Adjust oscilloscope according to manufacturer's instructions. Connect a Bosch test lead (1 684 463 093) between injector valve and plug. Connect oscilloscope according to manufacturer's instructions with the test lead.

CAUTION: Make sure the tester leads are not grounded in any way.




Start engine. If the injection output stage operates correctly or if the tester connections are correct, respectively, the following signal must be displayed: