2018 / ECLIPSE CROSS / EC - Workshop Manual
54 -CHASSIS ELECTRICAL > 54A-CHASSIS ELECTRICAL > Head Up Display (HUD) > SYMPTOM PROCEDURES > Trouble in HUD power supply system (Communication with the M.U.T.-IIISE is not possible.)
Inspection Procedure 1: Trouble in HUD power supply system (Communication with the M.U.T.-IIISE is not possible.)
| caution | Before replacing the ECU, ensure that the power supply circuit, the earth circuit and the communication circuit are normal. |
COMMENTS ON TROUBLE SYMPTOM
HUD communicates with M.U.T.-IIISE via CAN bus lines. If the communication with the MUT-IIISE is not possible, there may be some malfunction in the HUD, in the HUD power supply circuit or the earth circuit.
PROBABLE CAUSES
- Malfunction of the HUD
- Malfunction of power supply and earth circuit
DIAGNOSIS PROCEDURE
STEP 1. Resistance measurement at HUD connector (GND terminal).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Measure the resistance between the HUD connector (GND terminal) and body earth.OK: Continuity exists (2 Ω or less)
Is the check result normal?
Go to Step 2.
Correct the earth circuit between the HUD connector and the body earth (earth terminal).
STEP 2. Voltage measurement at HUD connector (+B terminal).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Check the voltage between the HUD connector (+B terminal) and body earth.OK: System voltage
Is the check result normal?
Go to Step 3. Correct the power supply circuit between the HUD connector and the power supply (+ B terminal).
STEP 3. Voltage measurement at HUD connector (IG1 terminal).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
(3) Check the voltage between the HUD connector (IG terminal) and body earth.OK: System voltage
Is the check result normal?
Go to Step 4. Correct the power supply circuit between the HUD connector and the power supply (IG1 terminal).
STEP 4. Retest the system
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