Monotester Hookup & Testing Information

CONNECTING THE MONOTESTER

Connect the monotester, as described in the operating manual, but note that the blue lead must be connected to the Lambda service pickup, which is located at the firewall on P70 MY 1983 and at the right wheel housing on P70 MY 1984 and later (as illustrated below).

NOTE! When driving the vehicle with the monotester connected, the positive (red) lead must be increased in length by 600 mm (24")



MODE AND SCALE SELECTION

Set the MONOTESTER switch as illustrated below.
TESTING OPEN LOOP, B28F (CI)



Disconnect the green wire from the Lambda sensor.

With the engine at normal operating temperature, the reading must be stable at 45 +/- 2 degrees.


NOTE: Applies only to CI engines The reading for LH-Engines may vary with the sensor disconnected.



If the reading of the MONOTESTER shows an incorrect value, check the following:

^ Check that the frequency valve is buzzing.

^ Wiring and connector continuity.
TESTING LAMBDA CONTROL FUNCTION (ALL ENGINES)



Ground the green wire from the control unit (at the firewall).



The pointer on the MONOTESTER should move to:

B28F (CI) 70 degrees or above

B23FT, B230FT, B230F 0 degrees.
Reconnect the green wire to the Lambda sensor.