[ Model - ECLIPSE CROSS / Year - 2018 ]
Inspection Procedure 1: Check the DC/DC converter power supply circuit.
2018 / ECLIPSE CROSS / EC - Workshop Manual
54 -CHASSIS ELECTRICAL > 54A-CHASSIS ELECTRICAL > DC/DC CONVERTER > SYMPTOM PROCEDURES > CHECK THE DC/DC CONVERTER POWER SUPPLY CIRCUIT.
 
 
cautionEven when the diagnosis code No. B1301 or B1302 is set in the engine-ECU, do not conclude as a DC/DC converter or engine-ECU error, and be sure to check the DC/DC converter power supply circuit.
 
 
CIRCUIT OPERATION
  • The power supply to the DC/DC converter is provided by the fusible link.
  • The ACC signal is received from ETACS-ECU.
 
 
 
PROBABLE CAUSES
  • The DC/DC converter (Entertainment) connector may be defective.
  • The battery may be defective.
  • Damaged harness wires and connectors
 
 
 
 
DIAGNOSIS PROCEDURE
STEP 1. Battery test.
Check the battery state. (Refer to .)
Is the check result normal?
Go to Step 2.
Replace the battery.
 
STEP 2. M.U.T.-IIISE ETACS system data list
Check the input signal of ACC relay.
  • Turn the ignition switch to the "ACC" position.
 
Item No.Item nameNormal condition
111ACC switchON
OK: Normal condition is displayed.
Is the check result normal?
Go to Step 3.
Refer to ETACS - Inspection Procedure 1 "The ignition switch (ACC) signal is not sent to the ETACS-ECU ."
 
STEP 3. Voltage measurement at DC/DC converter (Entertainment) connector (IGN terminal).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Turn the ignition switch to the "ACC" position.
(3) Check the voltage between DC/DC converter (Entertainment) connector (IGN terminal) and body earth.
OK: System voltage
Is the check result normal?
Go to Step 5.
Go to Step 4.
 
STEP 4. Check of short to power supply, short to earth, and open circuit in IGN line between DC/DC converter (Entertainment) connector and ETACS-ECU connector
Is the check result normal?
The trouble can be an 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 5. Voltage measurement at DC/DC converter (Entertainment) connector (PWR terminal).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Check the voltage between DC/DC converter connector (PWR terminal) and body earth.
OK: System voltage
Is the check result normal?
Go to Step 7.
Go to Step 6.
 
STEP 6. Check of short to power supply, short to earth, and open circuit in PWR line between fusible link and DC/DC converter (Entertainment) connector.
Is the check result normal?
The trouble can be an 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 7. Resistance measurement at DC/DC converter connector (GND terminal).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Check the continuity between the DC/DC converter connector (GND terminal) and body earth.
OK: Continuity exists (2 Ω or less)
Is the check result normal?
No action is necessary and testing is complete.
Go to Step 8.
 
STEP 8. Check of open circuit in GND line between DC/DC converter connector and body earth.
Is the check result normal?
The trouble can be an 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.