P2772

A750F AUTOMATIC TRANSMISSION / TRANSAXLE: AUTOMATIC TRANSMISSION SYSTEM: P2772: Four Wheel Drive (4WD) Low Switch Circuit Range / Performance
P2772 - Four Wheel Drive (4WD) Low Switch Circuit Range / Performance

DESCRIPTION

The ECM detects the signal from the transfer L4 position switch.

This DTC indicates that the transfer L4 position switch remains on.





MONITOR DESCRIPTION

Full Time 4WD

- The ECM monitors the transfer-case L4 position switch to determine when the transfer-case L4 gears are engaged. If the transfer-case L4 gears remain engaged under the following conditions, the ECM will conclude that there is a malfunction of the L4 position switch, illuminate the MIL and store the DTC:

- The L4 switch indicates that the L4 transfer-case gears are engaged.

- The transfer-case shifter is in the "H4" position.

- The transfer-case output shaft speed is between 1000 and 3000 rpm.

- The specified time period has elapsed.

Part Time 4WD

- The ECM monitors the transfer L4 position switch to determine when the transfer-case L4 gear is engaged. If the transfer-case L4 gears remain engaged under all of the following conditions, the ECM will conclude that there is a malfunction of the transfer L4 position switch, illuminate the MIL and store the DTC:

- The transfer L4 position switch indicates that the L4 transfer-case gears are engaged.

- The transfer-case shift lever is in "H".

- The transfer-case output shaft speed is between 1000 and 3000 rpm.

- The specified time period has elapsed.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS

All





ON Malfunction (A)





ON Malfunction (B)





TYPICAL MALFUNCTION THRESHOLDS

Both of the following conditions are met: ON malfunction (A) and (B)

ON Malfunction (A)





ON Malfunction (B)





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
Perform the universal trip to clear permanent DTCs Reading and Clearing Diagnostic Trouble Codes.

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (FOUR WHEEL DRIVE CONTROL ECU - BODY GROUND)

(a) Disconnect the F47 four wheel drive control ECU connector.





(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





Result





B -- GO TO TRANSFER SYSTEM VF4BM Transfer Case

C -- GO TO TRANSFER SYSTEM VF2A Transfer Case
A -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (FOUR WHEEL DRIVE CONTROL ECU - ECM)

(a) Disconnect the F51 ECM connector.





(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE ECM Removal