PROCEDURE
INSPECT SEMICONDUCTOR PWR INTEGRATION ECU (SIGNAL READING CHECK)
Note
Both present and history signal readings will be cleared if the semiconductor pwr integration ECU is removed. Make sure not to remove it before inspection.
Tech Tips
The signal readings of the semiconductor pwr integration ECU can be checked by inspecting the voltage at the diagnosis terminal.
Signal reading check
Turn the power switch on (IG).
| *a | Component with harness connected (Semiconductor Pwr Integration ECU) |
| *b | Diagnosis Terminal |
Connect the positive (+) terminal of a voltmeter to the semiconductor pwr integration ECU and the negative (-) terminal to the body ground.
Using the illustration below as a reference, determine whether any channels are malfunctioning based on the observed signal reading.
Tech Tips
Present signal reading and history signal reading will be displayed alternately after the power switch is turned on (IG). By measuring the duration of each header, the present signal reading and history signal reading can be recognized.
A unit malfunction indicates an internal malfunction of the semiconductor pwr integration ECU. If a malfunction is detected for any channel from channel 0 to 7, an electrical load connected to the semiconductor pwr integration ECU may be malfunctioning or there may be a short in the semiconductor pwr integration ECU circuit or in the wire harness.
The present signal reading will be stored as a history signal reading when electrical loads are operated after a malfunctioning part returns to normal.
Both present and history signal readings can be cleared by disconnecting the cable from the negative (-) auxiliary battery terminal.
Depending on the specification, different electrical loads connected to channels 0 to 7 are provided. Refer to the table below:
| Channel | Connected Electrical Load |
|---|---|
| ch0 | Heater water pump assembly |
| ch1 | Rear window defogger wire |
| ch2 | Windshield deicer wire |
| ch3 | Front fog lights |
| ch4 | Daytime running lights |
| ch5 | Stop lights |
| ch6 | High beam headlight RH |
| ch7 | High beam headlight LH |
INSPECT SEMICONDUCTOR PWR INTEGRATION ECU (RESULTS OF SIGNAL READING CHECK)
Results of signal reading check
Depending on the signal reading, perform troubleshooting according to the table below.
| Output Signal Reading | Repair Method |
|---|---|
| Normal | Continue troubleshooting for each system. |
| The unit is malfunctioning | Replace the semiconductor pwr integration ECU. |
| A malfunction in a channel (ch0 to ch7) |
|
Tech Tips
Make sure to clear the signal readings by disconnecting the cable from the negative (-) auxiliary battery terminal after replacement or repair of the malfunctioning part.
If no signal readings are output, perform troubleshooting according to the following troubleshooting procedure.
| *a | Component without semiconductor pwr integration ECU (No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly) |
- | - |
Remove the semiconductor pwr integration ECU.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
If the result is not as specified, repair or replace the wire harness or connector.