Faulty Signal

Starting The Engine
- Try to start the engine.
- Does the engine start?

Yes:
^ Proceed to test step below.

No:
^ Proceed to Checking Fuel Pump section below.





Checking The Engine Cooling Fan
- Ignition on.
- Activate engine cooling fan (FC) to high-speed.
- Is engine cooling fan running?

Yes:
^ Proceed to Checking Load Signal To Transmission section below.

No:
^ Proceed to test step below.





Checking Engine Cooling Fan Signal Cable
- Ignition off.
- Disconnect engine cooling fan relay connector B.
- Ignition on.
- Connect a test light (3 W bulb at least) between engine cooling fan relay connector B terminal 2 and ground.
- The bulb should not light.

If reading is OK:
^ Try a new engine cooling fan relay.

If reading is incorrect:
^ Check signal cable between engine cooling fan relay B2 and engine control module (ECM) # A22 for a short-circuit to supply voltage.





Checking Load Signal To Transmission
- If the car has manual transmission, proceed to Checking The MIL Signal Cable section below.
- Connect the test box and check ground terminals.
- Connect engine control module.
- Ignition on.
- Connect a test light between B28 and B12.
- The bulb should not light.

If reading is OK:
^ Proceed to test step below.

If reading is incorrect:
^ Check signal cable between the engine control module # B12 and transmission control module (TCM) # B12 for a short-circuit to supply voltage.





Checking The MIL Signal Cable
- Connect the test box and check ground terminals.
- Connect engine control module.
- Ignition on.
- Connect a voltmeter between connectors # 7 (# B7) and # 28 (# B28) on the test box.
- The voltmeter should read 0 - 2 Volts.

If reading is OK:
^ Intermittent fault.
^ For fault tracing, see: Faulty signal. Intermittent fault

If reading is incorrect:
^ Check cable between combined instrument panel # B11 and engine control module # B7 for a short-circuit to supply voltage.





Checking Fuel Pump
- Ignition on.
- Activate fuel pump.
- The fuel pump relay should operate and the fuel pump should run. It may be necessary to open the central relay module and feel the relay when it is being activated to determine whether it operates.

If reading is OK:
^ Proceed to Checking The Ignition Discharge Module Signal Cable section below.

If reading is incorrect:
^ Proceed to test step below.





Checking The Fuel Pump Signal Cable
- Ignition off.
- Disconnect fuel pump relay (2/23).
- Ignition on.
- Connect a test light (3 W bulb at least) between fuel pump relay connector terminal 4 (31B) and ground.
- The bulb should not light.

If reading is OK:
^ Try a new fuel pump relay.

If reading is incorrect:
^ Check signal cable between fuel pump relay terminal 4 (31B) and engine control module # B27 for a short-circuit to supply voltage.





Checking The Ignition Discharge Module Signal Cable
- Ignition off
- Disconnect ignition discharge module (IDM) connector.
- Ignition on.
- Connect a test light (3 W bulb at least) between ignition discharge module connector terminal 4 and ground.
- The bulb should not light.

If reading is OK:
^ Try a new ignition discharge module.

If reading is incorrect:
^ Check signal cable between ignition discharge module terminal 4 and engine control module # B11 for a short-circuit to supply voltage.

Fault-tracing Information
Fault-tracing for this diagnostic test is not followed by a verification.

- Do you want to repeat the fault-tracing for this diagnostic test?

Yes:
^ Return to Starting The Engine section above.

No:
^ Fault corrected