[ Model - ECLIPSE CROSS / Year - 2018 ]
INSPECTION PROCEDURE 8: A/C controller assembly (A/C-ECU) power supply system
2018 / ECLIPSE CROSS / EC - Workshop Manual
55 -HEATER, AIR CONDITIONER AND VENTILATION > TROUBLESHOOTING > SYMPTOM PROCEDURES > A/C-ECU POWER SUPPLY SYSTEM
 
 
 
 
COMMENTS ON TROUBLE SYMPTOM
If the A/C controller assembly (A/C-ECU) is not energised, the power supply or earth system to the ECU may be defective.
 
 
 
PROBABLE CAUSES
  • Malfunction of the A/C controller assembly (A/C-ECU)
  • Damaged wiring harness or connectors
 
 
 
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-IIISE other system's diagnosis code
Check that the ETACS-ECU has not set a diagnosis code.
Is the diagnosis code set?
Carry out the diagnosis code procedures. Refer to GROUP 54A, ETACS-ECU .
Go to Step 2.
 
STEP 2. Measure the voltage at the A/C controller assembly (A/C-ECU) connector.
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Ignition switch: "ON"
(3) Voltage between IG1 terminal and body earth
OK: System voltage
Is the check result normal?
Go to Step 4.
Go to Step 3.
 
STEP 3. Check of open circuit in IG1 line between ETACS-ECU connector and A/C controller assembly (A/C-ECU) connector.
Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Repair the connector(s) or wiring harness.
 
STEP 4. Measure the voltage at the A/C controller assembly (A/C-ECU) connector.
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Voltage between B/UP terminal and body earth
OK: System voltage
Is the check result normal?
Go to Step 6.
Go to Step 5.
 
STEP 5. Check of open circuit in B/UP line between ETACS-ECU connector and A/C controller assembly (A/C-ECU) connector.
notePrior to the wiring harness inspection, check joint connector and repair if necessary.
Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Repair the connector(s) or wiring harness.
 
STEP 6. Measure the resistance at the A/C controller assembly (A/C-ECU) connector.
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Resistance between E terminal and body earth
OK: Continuity exists (2 Ω or less)
Is the check result normal?
Replace the A/C controller assembly (A/C-ECU).
Go to Step 7.
 
STEP 7. Check of open circuit in E line between A/C controller assembly (A/C-ECU) connector and body earth.
Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Repair the connector(s) or wiring harness.