Without Scan Tool

Replacement of Control Unit
The control unit itself rarely fails. In most cases, the harnesses have failed (i.e. short-circuit). Before replacing the control unit, check the connector joints and whether the specified current flows to the control unit.

Trouble Intermittently Observed
Troubles intermittently observed are mostly attributable to temporary imperfect connection of harnesses and connectors.
When such troubles are found, check the associated circuit according to the following procedure.
1. Check whether connectors are plugged in or connector terminals are completely engaged.
2. Check whether the terminals are deformed or damaged. If yes, remove the deformation or damage and connect the terminals securely.
3. In examination of failed harness circuit, shake the harness to check for poor connections. Do not put unnecessary stress on the harness.

System Check of Failed TOD Vehicle
If the TOD indicator lamps experienced faulty operation even once in the past, the failed portion can be identified by use of the procedure "Diagnosis from Trouble Codes" or "Trouble Diagnosis Depending on The Status of TOD Indicator". If the troubles that are only recognized as abnormal phenomena of the vehicle by the driver are observed, conduct the test outlined in the following procedure to reproduce the faulty phenomena and diagnose the fault for each phenomenon.
1. Start the engine, and check that the TOD indicator lamps are turned on for about two seconds for initial check; the CHECK lamp goes off; and the TOD indicator lamps display the specified drive mode. (If the CHECK lamp starts blinking, read the trouble codes and identify the failed portion.)
2. While keeping the vehicle at a standstill, shift the transfer lever to change the modes: TOD mode - 4L mode - TOD mode. Check that the TOD indicator lamps correctly display the status whenever the mode is changed. If the transition status is displayed during the shift operation, run the vehicle a little to complete shifting.
3. Start the vehicle in the TOD mode, and slowly accelerate to at least 40 km/h (25 MPH) and maintain the speed for about two minutes. Apply the brake to completely stop the vehicle. Repeat this test pattern at least three times.
4. Turn the steering fully to the right (or left) in the TOD mode, and slowly drive the vehicle in a circle five times.
5. Start the vehicle in the TOD mode, and slowly accelerate to at least 40 km/h (25 MPH). Apply the brake strongly so that the ABS works, and completely stop the vehicle.
6. Start the vehicle in the 4L mode, and slowly accelerate to at least 20 km/h (13 MPH). Apply the brake and completely stop the vehicle.
If the CHECK lamp starts blinking during the test run, read the trouble codes and give appropriate maintenance according to the diagnostic procedure. If the TOD indicator lamps are lit abnormally during the run, check the lighting condition and give appropriate maintenance according to the diagnostic procedure. Even if the phenomena are not observed, try to reproduce the abnormal state reported by the customer.

Post-Repair Check
As long as the starter switch is not turned off, the TOD indicator lamps continue blinking even after the failed control unit is repaired. Therefore, upon completion of repair, be sure to turn off the starter switch once and then turn it on to conduct the test run sequence specified in steps 1 through 6 above and check that the TOD indicator lamps no longer show any faulty status.





Basic Diagnostic Flow Chart

Functions of Indicator Lamp





TOD Indicator Lamps
Indication of Drive Mode
The transfer lever position signals are transmitted to the TOD control unit according to the condition listed above.

Bulb Check





When the starter switch is turned on, the TOD indicator lamps go on as shown.

Notice: Once the starter switch is turned on, all the TOD indicator lamps are lit for two seconds, even if the transfer lever is in any position.

Simplified checking method of ABS INPUT and BRAKE ON signals:





In the event that any of the signal inputs listed below are observed while the self-diagnostic code is being displayed (the self-diagnostic connector is short-circuited to GND), you can simply check the ABS INPUT and BRAKE ON signals as shown in the figures below.

Check Lamp
Check Lamp Bulb Check





When the starter switch is turned on in the normal state, the control unit turns on the CHECK lamp to check the bulb.