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DTC P0850:24 [BODY CONTROL MODULE (BCM)]

id0902r7093300

Outline

System malfunction location

Transaxle range sensor circuit malfunction

Detection condition

•  The body control module (BCM) detects that the transaxle range sensor signal is other than P and N position for a continuous 5 times or more even though the TCM CAN signal is in P or N position.

Fail-safe

•  Perform control of the internal signal for control of the transaxle range sensor as position other than P, N positions.

Possible cause

•  DTCs are stored in the TCM.

•  Body control module (BCM) connector or terminal malfunction

•  TCM connector or terminal malfunction

•  Short to power supply in TCM signal circuit

•  TCM malfunction

•  Body control module (BCM) malfunction

System malfunction location	Transaxle range sensor circuit malfunction
Detection condition	• The body control module (BCM) detects that the transaxle range sensor signal is other than P and N position for a continuous 5 times or more even though the TCM CAN signal is in P or N position.
Fail-safe	• Perform control of the internal signal for control of the transaxle range sensor as position other than P, N positions.
Possible cause	• DTCs are stored in the TCM. • Body control module (BCM) connector or terminal malfunction • TCM connector or terminal malfunction • Short to power supply in TCM signal circuit • TCM malfunction • Body control module (BCM) malfunction

Diagnostic Procedure

Step

Inspection

Results

Action

1

VERIFY BODY CONTROL MODULE (BCM) DTCs AGAIN

•  Clear the DTC recorded in the memory.
(See CLEARING DTC.)

•  Switch the ignition ON (engine off).

•  Perform the following work 5 times or more.

―  Operate the selector lever to P or N position and wait for 1 s or more.

―  Operate the selector lever to other than P and N position and wait for 1 s or more.

―  Operate the selector lever to P or N position.

•  Perform the DTC inspection for the body control module (BCM).
(See DTC INSPECTION.)

•  Is the same Pending DTC present?

Yes

Go to the next step.

No

Go to repair completion verification 2.

2

INSPECT TCM FOR MALFUNCTION

•  Perform the DTC inspection for the TCM.
(See DTC INSPECTION.)

•  Is a DTC displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See ON-BOARD DIAGNOSTIC SYSTEM DTC TABLE [TCM (ET6A-EL, ET6AX-EL) (E)].)

(See ON-BOARD DIAGNOSTIC SYSTEM DTC TABLE [TCM (EV6A-EL, EV6AX-EL) (E)].)

No

Go to the next step.

3

INSPECT BODY CONTROL MODULE (BCM) CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(See CONNECTOR INSPECTION.)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

4

INSPECT TCM CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(See CONNECTOR INSPECTION.)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

5

INSPECT TCM SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY

•  Inspect the applicable circuit for a short to power supply.
(See CIRCUIT INSPECTION.)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

6

INSPECT TCM FOR MALFUNCTION DEPENDING ON REPEATABILITY

•  Install/connect the part removed/disconnected during the troubleshooting procedure.

•  Clear the DTC recorded in the memory.
(See CLEARING DTC.)

•  Switch the ignition ON (engine off).

•  Perform the following work 5 times or more.

―  Operate the selector lever to P or N position and wait for 1 s or more.

―  Operate the selector lever to other than P and N position and wait for 1 s or more.

―  Operate the selector lever to P or N position.

•  Perform the DTC inspection for the body control module (BCM).
(See DTC INSPECTION.)

•  Is the same Pending DTC present?

Yes

Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].)

If the CAN communication is normal, replace the TCM and perform the repair completion verification.

(See CONTROL VALVE BODY REMOVAL/INSTALLATION [ET6A-EL, ET6AX-EL (E)].)

(See CONTROL VALVE BODY REMOVAL/INSTALLATION [EV6A-EL, EV6AX-EL (E)].)

No

Go to repair completion verification 2.

Repair completion verification 1

VERIFY THAT VEHICLE IS REPAIRED

•  Install/connect the part removed/disconnected during the troubleshooting procedure.

•  Clear the DTC recorded in the memory.
(See CLEARING DTC.)

•  Switch the ignition ON (engine off).

•  Perform the following work 5 times or more.

―  Operate the selector lever to P or N position and wait for 1 s or more.

―  Operate the selector lever to other than P and N position and wait for 1 s or more.

―  Operate the selector lever to P or N position.

•  Perform the DTC inspection for the body control module (BCM).
(See DTC INSPECTION.)

•  Is the same Pending DTC present?

Yes

Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].)

If the CAN communication is normal, perform the diagnosis from Step 1.

•  If the malfunction recurs, replace the body control module (BCM), then go to the next step.
(See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION [(E)].)

No

Go to the next step.

Repair completion verification 2

VERIFY IF OTHER DTC IS DISPLAYED

•  Perform the DTC inspection.
(See DTC INSPECTION.)

•  Are any other DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

No

DTC troubleshooting completed.

Step	Inspection	Results	Action
1	VERIFY BODY CONTROL MODULE (BCM) DTCs AGAIN • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Switch the ignition ON (engine off). • Perform the following work 5 times or more. ― Operate the selector lever to P or N position and wait for 1 s or more. ― Operate the selector lever to other than P and N position and wait for 1 s or more. ― Operate the selector lever to P or N position. • Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION.) • Is the same Pending DTC present?	Yes	Go to the next step.
1		No	Go to repair completion verification 2.
2	INSPECT TCM FOR MALFUNCTION • Perform the DTC inspection for the TCM. (See DTC INSPECTION.) • Is a DTC displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See ON-BOARD DIAGNOSTIC SYSTEM DTC TABLE [TCM (ET6A-EL, ET6AX-EL) (E)].) (See ON-BOARD DIAGNOSTIC SYSTEM DTC TABLE [TCM (EV6A-EL, EV6AX-EL) (E)].)
2		No	Go to the next step.
3	INSPECT BODY CONTROL MODULE (BCM) CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
3		No	Repair or replace the malfunctioning location and perform the repair completion verification.
4	INSPECT TCM CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
4		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT TCM SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY • Inspect the applicable circuit for a short to power supply. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
5		No	Repair or replace the malfunctioning location and perform the repair completion verification.
6	INSPECT TCM FOR MALFUNCTION DEPENDING ON REPEATABILITY • Install/connect the part removed/disconnected during the troubleshooting procedure. • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Switch the ignition ON (engine off). • Perform the following work 5 times or more. ― Operate the selector lever to P or N position and wait for 1 s or more. ― Operate the selector lever to other than P and N position and wait for 1 s or more. ― Operate the selector lever to P or N position. • Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION.) • Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) If the CAN communication is normal, replace the TCM and perform the repair completion verification. (See CONTROL VALVE BODY REMOVAL/INSTALLATION [ET6A-EL, ET6AX-EL (E)].) (See CONTROL VALVE BODY REMOVAL/INSTALLATION [EV6A-EL, EV6AX-EL (E)].)
6		No	Go to repair completion verification 2.
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED • Install/connect the part removed/disconnected during the troubleshooting procedure. • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Switch the ignition ON (engine off). • Perform the following work 5 times or more. ― Operate the selector lever to P or N position and wait for 1 s or more. ― Operate the selector lever to other than P and N position and wait for 1 s or more. ― Operate the selector lever to P or N position. • Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION.) • Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) If the CAN communication is normal, perform the diagnosis from Step 1. • If the malfunction recurs, replace the body control module (BCM), then go to the next step. (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION [(E)].)
Repair completion verification 1		No	Go to the next step.
Repair completion verification 2	VERIFY IF OTHER DTC IS DISPLAYED • Perform the DTC inspection. (See DTC INSPECTION.) • Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
Repair completion verification 2		No	DTC troubleshooting completed.