DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
INSPECT FUSE (H-LP LVL)
CHECK WIRE HARNESS (AFS ECU - BATTERY AND BODY GROUND)
CHECK RESISTANCE OF COMMUNICATION LINE
DTC B1205 AFS ECU Communication Stop
DESCRIPTION
This DTC is detected when communication between the AFS ECU and the gateway ECU stops for more than 10 seconds.
| DTC No. | DTC Detection Condition | Trouble Area |
| B1205 | AFS ECU communication stops | |
WIRING DIAGRAM
INSPECTION PROCEDURE
- When "+B of GND short malfunction of communication bus" DTCs (B1266 and B1267) are detected at the same time as "communication stop" DTC B1205, repair the "+B or GND short malfunction of communication bus" DTCs first.
| 1.INSPECT FUSE (H-LP LVL) |
Remove the H-LP LVL fuse from the main body ECU LH (cowl side J/B LH).
Measure the resistance of the fuse.
- Standard resistance:
- Below 1 Ω
| 2.CHECK WIRE HARNESS (AFS ECU - BATTERY AND BODY GROUND) |
Disconnect the A27 ECU connector.
Turn the engine switch on (IG).
Measure the voltage and resistance of the wire harness side connector.
- Standard voltage:
| Tester Connection | Condition | Specified Condition |
| IG (A27-2) - Body ground | Engine switch on (IG) | 10 to 14 V |
- Standard resistance:
| Tester Connection | Specified Condition |
| E1 (A27-1) - Body ground | Below 1 Ω |
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
| 3.CHECK RESISTANCE OF COMMUNICATION LINE |
Disconnect the A27, J58 and J34 ECU connectors.
Measure the resistance between the specified terminals on the wire harness side connectors.
- Standard resistance:
| Tester Connection | Specified Condition |
| MPX1 (A27-5) - MPX- (J58-31) | Below 1 Ω |
| MPX2 (A27-6) - MPX+ (J34-6) | Below 1 Ω |
- Result:
| Result | Proceed to |
| Both are OK | A |
| One is OK | B |
| Both are NG | C |
| | REPLACE AFS ECU AND REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
LEXUS IS250, IS220d / GSE20 ALE20
