GSIC - Global Service Information Center

DTC B1451/51 Compressor Solenoid Circuit

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DESCRIPTION

In this circuit, the compressor receives a refrigerant compression demand signal from the air conditioning amplifier.
Based on this signal, the compressor changes the degree of refrigerant compression.

DTC No.	DTC Detection Condition	Trouble Area
B1451/51	Open or short in solenoid of externally changeable compressor circuit	A/C compressor Harness and connector between A/C amplifier and solenoid of externally changeable compressor A/C amplifier

WIRING DIAGRAM

INSPECTION PROCEDURE

1.READ VALUE OF INTELLIGENT TESTER

Connect the intelligent tester to the DLC3.

Turn the engine switch on (IG) and push the intelligent tester main switch on.

Select the items below in the Data List, and read the displays on the intelligent tester.

ECM:
Item	Measurement Item / Display (Range)	Normal Condition	Diagnostic Note
A/C Magnetic Clutch Relay (A/C Mag Clutch)	A/C Magnetic Clutch Relay / OFF, ON	ON: A/C magnetic clutch ON OFF: A/C magnetic clutch OFF	-

OK:: The display is as specified in the normal condition.

Result:
NG	A
OK (Checking from the PROBLEM SYMPTOMS TABLE)	B
OK (Checking from the DTC)	C

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

REPLACE AIR CONDITIONING AMPLIFIER

A

2.INSPECT A/C COMPRESSOR

3GR-FE, 3GR-FSE
1. Disconnect the E46 A/C compressor connector.
2. Measure the resistance of the connector.
  Standard resistance:
  Tester Connection
  Condition
  Specified Condition
  3 (SOL+) - 6 (SOL-)
  20°C (68°F)
  10 to 11 Ω

3UZ-FE
1. Disconnect the E1 A/C compressor connector.
2. Measure the resistance of the connector.
  Standard resistance:
  Tester Connection
  Condition
  Specified Condition
  2 (SOL+) - 1 (SOL-)
  20°C (68°F)
  10 to 11 Ω

REPLACE A/C COMPRESSOR

OK

3.CHECK WIRE HARNESS (A/C COMPRESSOR - BODY GROUND)

3GR-FE, 3GR-FSE
1. Disconnect the E46 A/C compressor connector.
2. Measure the resistance of the wire harness connector.
  Standard resistance:
  Tester Connection
  Condition
  Specified Condition
  E46-6 (SOL-) - Body ground
  Always
  Below 1 Ω

3UZ-FE
1. Disconnect the E1 A/C compressor connector.
2. Measure the resistance of the wire harness connector.
  Standard resistance:
  Tester Connection
  Condition
  Specified Condition
  E1-1 (SOL-) - Body ground
  Always
  Below 1 Ω

REPAIR OR REPLACE HARNESS AND CONNECTOR

OK

4.CHECK WIRE HARNESS (A/C COMPRESSOR - A/C AMPLIFIER)

Disconnect the E46 or E1 A/C compressor connector.

Disconnect the L52 A/C amplifier connector.

Measure the resistance of the wire harness side connectors.
Standard resistance:
Tester Connection
Condition
Specified Condition
L52-5 (SOL+) - E1-2 (SOL+) (*2)
Always
Below 1 Ω
L52-5 (SOL+) - E46-3 (SOL+) (*1)
Always
Below 1 Ω
HINT:
1. *1: 3GR-FE, 3GR-FSE
2. *2: 3UZ-FE

REPAIR OR REPLACE HARNESS AND CONNECTOR

REPLACE AIR CONDITIONING AMPLIFIER

Tester Connection	Condition	Specified Condition
3 (SOL+) - 6 (SOL-)	20°C (68°F)	10 to 11 Ω

Tester Connection	Condition	Specified Condition
L52-5 (SOL+) - E1-2 (SOL+) (*2)	Always	Below 1 Ω
L52-5 (SOL+) - E46-3 (SOL+) (*1)	Always	Below 1 Ω