Diagnostic Manual, Engines, Volume 4
Electrical Test Program - Preparation for Test
|Preliminary work: Diagnosis - Malfunction Memory 11
|1. Ignition: OFF
2. Connect test cable with socket box to engine control module (N3/10) according to connection diagram
Electrical wiring diagrams :
Electrical Troubleshooting Manual, Model 129,
Electrical Troubleshooting Manual, Model 140,
Electrical Troubleshooting Manual, Model 210.
Connect interior harness connector to connection 1 on test cable.
Connect engine harness connector to connection 2 on test cable.
The test program is divided into four sections:
23 SFI Test
24 Ignition System Test
25 EA System Test
26 CC System Test
Note regarding "Test Connection" column:
The numbers indicated in parentheses, for example, 1.0 (1.23) signify:
1= Connector 1 on wiring diagram,
23= Socket 23 on wiring diagram.
Test Equipment; See MBUSA Standard Service Equipment Program
||Brand, model, etc.
||Fluke models 23, 77 III, 83, 85, 87
|To Avoid Damage to the Ignition System
To avoid damage to the engine control module (N3/10), connect/disconnect the control module connectors only with the
ignition: OFF .
Do not connect a test lamp to circuit 1 or 15 of the ignition coil.
The high output side of the ignition system must carry at least 2 k of load (spark plug connector).
To avoid damaging the ignition coils during individual testing, do not load the coil with more than 28 kV.
Primary connections carry a voltage of up to 400 V. The iron core bracket of the ignition coils must always be connected to vehicle ground.
Persons with pacemakers should not work on this type of ignition system.
Using Test Equipment
Ensure that the engine and ignition are OFF when connecting/ disconnecting test equipment to a coil.