Dtc B2271 Ignition Hold Monitor Malfunction
Engine. Lexus Is250, Is220D. Gse20 Ale20
DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
INSPECT FUSE (AM2)
CHECK CONNECTORS
CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - BATTERY AND BODY GROUND)
INSPECT RELAY (IG2)
INSPECT JUNCTION BLOCK
CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - BODY GROUND)
CHECK WIRE HARNESS (COWL SIDE J/B LH - BODY GROUND)
CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - BODY GROUND)
RECHECK FOR DTC
REPLACE FAULTY RELAY OR J/B AND CHECK POWER SOURCE CONTROL ECU
REPAIR OR REPLACE WIRE HARNESS OR CONNECTOR AND CHECK POWER SOURCE CONTROL ECU
DTC B2271 Ignition Hold Monitor Malfunction |
DESCRIPTION
This DTC is output when a problem such as an open in the AM2 fuse, an open or short in the wire harness between the fuse and power source control ECU, a short in the IG output circuit inside the power source control ECU, a short between the power source control ECU and relay, and a short in the relay is detected.- HINT:
- When the power source control ECU is replaced with a new one and the negative (-) battery terminal is connected, the power source mode becomes the IG-ON mode. When the battery is removed and reinstalled, the power source mode that was selected when the battery was removed is restored.
DTC No.
| DTC Detection Condition
| Trouble Area
|
B2271
| Hold circuit, IG1 relay actuation circuit or IG2 relay actuation circuit inside power source control ECU is open or short
| - AM2 fuse
- IG2 relay
- Cowl side J/B RH
- Cowl side J/B LH
- Power source control ECU
- Wire harness or connector
|
WIRING DIAGRAM
INSPECTION PROCEDURE
Remove the AM2 fuse from the cowl side J/B RH.
Measure the resistance of the fuse.
- Standard resistance:
- Below 1 Ω
Check that the connectors are securely connected and the terminals are not deformed or loose.
- OK:
- The connectors are securely connected and the terminals are not deformed or loose.
| REPAIR OR REPLACE CONNECTORS |
|
|
3.CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - BATTERY AND BODY GROUND) |
Disconnect the J55 ECU connector.
Measure the voltage according to the value(s) in the table below.
- Standard voltage:
Tester Connection (Symbols)
| Condition
| Specified Condition
|
J55-33 (AM1) - Body ground
| Always
| 10 to 14 V
|
J55-12 (AM2) - Body ground
| Always
| 10 to 14 V
|
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
Tester Connection (Symbols)
| Condition
| Specified Condition
|
J55-6 (GND2) - Body ground
| Always
| Below 1 Ω
|
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
Remove the IG2 relay from the engine room R/B No. 2.
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
Tester Connection
| Specified Condition
|
3 - 5
| 10 kΩ or higher
|
3 - 5
| Below 1 Ω (When battery voltage is applied to terminals 1 and 2)
|
RH-IG relay:
Disconnect the cowl side J/B RH connectors.
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
Tester Connection
| Condition
| Specified Condition
|
RD-6 - RA-5 or RD-7
| Always
| 136 to 250 Ω at 20°C (68°F)
|
RD-6 - Body ground
| Always
| 10 kΩ or higher
|
LH-IG relay:
Disconnect the cowl side J/B LH connectors.
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
Tester Connection
| Condition
| Specified Condition
|
LD-13 - LD-8 or LD-9
| Always
| 68 to 250 Ω at 20°C (68°F)
|
LD-13 - Body ground
| Always
| 10 kΩ or higher
|
6.CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - BODY GROUND) |
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
Tester Connection (Symbols)
| Condition
| Specified Condition
|
J55-34 (IG1D) - Body ground
| Always
| 10 kΩ or higher
|
J55-35 (IG2D) - Body ground
| Always
| 10 kΩ or higher
|
7.CHECK WIRE HARNESS (COWL SIDE J/B LH - BODY GROUND) |
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
Tester Connection
| Condition
| Specified Condition
|
LD-13 - Body ground
| Always
| 10 kΩ or higher
|
8.CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - BODY GROUND) |
Reconnect the J55 ECU and J/B connectors.
Measure the voltage according to the value(s) in the table below.
- Standard voltage:
Tester Connection (Symbols)
| Condition
| Specified Condition
|
J55-34 (IG1D) - Body ground
| Engine switch off
| Below 1 V
|
Engine switch on (IG)
| Output voltage at terminal AM2 is -2 V or more.
|
J55-35 (IG2D) - Body ground
| Engine switch off
| Below 1 V
|
Engine switch on (IG)
| Output voltage at terminal AM2 is -2 V or more.
|
| REPLACE POWER SOURCE CONTROL ECU |
|
|
Delete the DTCs (Click here).
After DTCs are all cleared, turn the engine switch on (IG). After 30 seconds have elapsed, check for DTCs again.
- OK:
- DTC B2271 is not output.
| REPLACE POWER SOURCE CONTROL ECU |
|
|
OK |
|
|
|
CHECK INTERMITTENT PROBLEMS |
|
10.REPLACE FAULTY RELAY OR J/B AND CHECK POWER SOURCE CONTROL ECU |
Replace a faulty relay or J/B and then connect the power source control ECU connector.
Measure the voltage according to the value(s) in the table below.
- Standard voltage:
Tester Connection (Symbols)
| Condition
| Specified Condition
|
J55-34 (IG1D) - Body ground
| Engine switch off
| Below 1 V
|
Engine switch on (IG)
| Output voltage at terminal AM2 is -2 V or more.
|
J55-35 (IG2D) - Body ground
| Engine switch off
| Below 1 V
|
Engine switch on (IG)
| Output voltage at terminal AM2 is -2 V or more.
|
| REPLACE POWER SOURCE CONTROL ECU |
|
|
11.REPAIR OR REPLACE WIRE HARNESS OR CONNECTOR AND CHECK POWER SOURCE CONTROL ECU |
Repair or replace a faulty wire harness or connector and then connect the power source control ECU connector.
Measure the voltage according to the value(s) in the table below.
- Standard voltage:
Tester Connection (Symbols)
| Condition
| Specified Condition
|
J55-34 (IG1D) - Body ground
| Engine switch off
| Below 1 V
|
Engine switch on (IG)
| Output voltage at terminal AM2 is -2 V or more.
|
J55-35 (IG2D) - Body ground
| Engine switch off
| Below 1 V
|
Engine switch on (IG)
| Output voltage at terminal AM2 is -2 V or more.
|
| REPLACE POWER SOURCE CONTROL ECU |
|
|