Engine Test (Diesel)
This section describes some tests which may be already familiar from the TECH 80 diagnostic program. These tests are used for rapid localisation of faults, which can occur in the course of basic engine operations (compression, alternator, etc.).
A pre-condition for all of the tests is that no fault codes are stored in the memory of the engine control unit. If the engine telltale illuminates while the engine is running, the fault code must first be read off and the fault rectified using the TECH 1/2 checking procedure.
The technician must observe the instructions on the test sheets as closely as possible.
If a test procedure is repeated, depress the [REPEAT TEST] key on the TECH 31 and then restart the test using the instructions listed under the "Procedure".
Once a test has been completed, the vehicle must be restored to its original condition (reconnect released plugs, reinsert relays or fuses).