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Main relay

Main relay

Fault symptoms

Engine fails to start

Diagnostic procedure

1. Check the fuses




- Check MAXI fuse 2


Is the fuse intact?

yes

Continue with point 2.


no

Change the fuse.


2. Check the performance of the main relay



- Turn the ignition switch to the ON position.



- Unplug the IAC valve's 3-pin connector.



- Connect the test lamp to:


The test lamp should light up.

Did the test lamp light up?

yes

The main relay is OK.


no

Continue with point 2.


3. Check the power supply for the main relay circuit



- Turn the ignition switch to the ON position.



- Unplug the main relay from its socket.



- Connect the test lamp to:


Did the test lamp light up?

yes

Continue with point 4.


no

Continue fault diagnosis as described in Service Manual 3:2 "Electrical system, wiring diagrams".


4. Check the relay output



- Remove the IAC valve.



- Connect a test lamp to:



- Connect a jumper lead to the relay socket between:


The test lamp should light up.

Did the test lamp light up?

yes

Continue with point 5.


no

Check the lead for continuity/shorting to ground and repair or replace it if necessary.


5. Check the control module's output



- Connect a test lamp to the relay socket between:



- Turn the ignition switch to the ON position.


The test lamp should light up.

Did the test lamp light up?

yes

Change the main relay.


no

Check the lead between pin 85 of the relay and pin 27 of the control module for continuity. If the lead is OK, continue as described in .