CAUTION / NOTICE / HINT
Note
If the battery is weak or if the engine is difficult to start, perform the following procedures.
PROCEDURE
CHECK BATTERY CONDITION
Check the battery for damage, deformation and leakage. If damage, deformation or leakage is found, replace the battery.
Check the electrolyte quantity of each cell.
Tech Tips
Before checking the battery voltage, turn off all the electrical systems (headlights, blower motor, rear defogger, etc.).
If the electrolyte quantity is below the lower line, replace the battery.
If the electrolyte quantity is above the lower line, check the battery voltage when cranking the engine. If the voltage is less than 9.6 V, recharge or replace the battery.
Check the voltage.
Turn the ignition switch off and turn on the headlights for 20 to 30 seconds. This will remove the surface charge from the battery.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
If the result is not as specified, charge the battery.
CHECK BATTERY TERMINAL AND FUSE
Check that the battery terminals are not loose or corroded.
If the terminals are corroded, clean the terminals.
Measure the resistance of the charging fuses.
Tech Tips
For fuse locations, refer to Parts Location Click here.
| Standard resistance |
|---|
| Below 1 Ω |
If the result is not as specified, replace the fuse.
CHECK V-RIBBED BELT
VISUALLY CHECK GENERATOR WIRING
Check that the wiring is in good condition.
If the wiring is damaged, repair or replace the generator wire.
LISTEN FOR ABNORMAL NOISE FROM GENERATOR
Check that the generator does not emit any abnormal noise while the engine is running.
If there is abnormal noise, replace the pulley or generator.
CHECK CHARGE WARNING LIGHT CIRCUIT
Turn the ignition switch to ON. Check that the charge warning light turns on.
Start the engine and check that the light turns off.
If the light does not operate as specified, troubleshoot the charge warning light circuit.
CHECK CHARGING CIRCUIT WITHOUT LOAD
| *1 | Disconnect wire from terminal B |
Check the charging circuit.
Put the vehicle in a no-load test condition and run the engine at 2000 rpm. Using a voltmeter and ammeter, measure the battery voltage and current.
| Standard current |
|---|
| 10 A or less |
| Standard voltage |
|---|
| 12.1 to 15.4 V |
If the results are not as specified, replace the generator.
Tech Tips
If the battery is not fully charged, the ammeter reading will sometimes be more than the standard current.
CHECK CHARGING CIRCUIT WITH LOAD
Put the vehicle in a load test condition (set the headlights to high beam and set the heater blower switch to Hi) and run the engine at 2000 rpm. Using an ammeter, measure the current.
Check the reading on the ammeter.
| Standard current |
|---|
| 30 A or higher |
If the ammeter reading is less than the standard current, replace the generator.
Tech Tips
If the ammeter reading is less than the standard current even though the battery is fully charged, the load is not sufficient. Therefore, operate the wiper motor, rear window defogger, etc. to increase the load, and perform the measurement again.
If the battery is fully charged, the ammeter reading will sometimes be less than the standard current.
CHECK CHARGING CONTROL SYSTEM
Inspect the wire harness.
w/ Entry and Start System:
Disconnect the D113 power management control ECU connector.
w/o Entry and Start System:
Disconnect the D112 power management control ECU connector.
Disconnect the B16 generator assembly connector.
Measure the resistance according to the value(s) in the table below.
| *1 | w/ Entry and Start System: Rear view of wire harness connector (to Power Management Control ECU) |
| *2 | Front view of wire harness connector (to Generator Assembly) |
| *3 | w/o Entry and Start System: Rear view of wire harness connector (to Power Management Control ECU) |
| *4 | Front view of wire harness connector (to Generator Assembly) |
| Standard Resistance | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||
|
Tech Tips
For the layout of the power management control ECU terminals, refer to Terminals of ECU Click here.
Inspect the power management control ECU.
| *1 | w/ Entry and Start System: Component with harness connected (Power Management Control ECU) |
| *2 | w/o Entry and Start System: Component with harness connected (Power Management Control ECU) |
Start the engine and warm it up for 20 to 30 minutes.
Connect an oscilloscope to the connector terminals of the power management control ECU.
Tech Tips
Refer to the waveform table in the next step for terminal connections.
For the layout of the power management control ECU terminals, refer to Terminals of ECU Click here.
Check that the power management control ECU output is a square wave as shown in the illustration when the vehicle is driven at a constant speed.
| Waveform | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||
Tech Tips
The oscilloscope waveform shown in the illustration is an example for reference only. Waveforms with noise or chattering are not shown.
As the duty cycle changes in accordance with the electrical load and battery condition, the output waveform also changes.
Check that the power management control ECU output is a square wave as shown in the illustration when the vehicle is accelerating.
| Waveform | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||
Tech Tips
The oscilloscope waveform shown in the illustration is an example for reference only. Waveforms with noise or chattering are not shown.
As the duty cycle changes in accordance with the electrical load and battery condition, the output waveform also changes.
Check that the power management control ECU output is a square wave as shown in the illustration when the vehicle is decelerating.
| Waveform | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||
Tech Tips
The oscilloscope waveform shown in the illustration is an example for reference only. Waveforms with noise or chattering are not shown.
As the duty cycle changes in accordance with the electrical load and battery condition, the output waveform also changes.