P1836

DTC P1836: Shift Fork 1 Malfunction

CAUTION:

- If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, diagnose the CAN bus lines.
- Whenever the ECU is replaced, ensure that the CAN bus lines are normal.

DIAGNOSTIC FUNCTION

TC-SST-ECU checks that the movement of the shift fork 1 is normal.

DESCRIPTIONS OF MONITOR METHODS

The movement of the shift fork 1 is determined to be abnormal.

MONITOR EXECUTION

- Continuous

MONITOR EXECUTION CONDITIONS (OTHER MONITOR AND SENSOR)

Other Monitor (There is no temporary DTC stored in memory for the item monitored below)

- P183D: Shift fork 2 malfunction
- P1844: Shift fork 3 malfunction
Sensor (The sensor below is determined to be normal)

- Not applicable

LOGIC FLOW CHARTS (Monitor Sequence)[ Functional check - blocked]





DTC SET CONDITIONS[ FUNCTIONAL CHECK - BLOCKED]

Check Conditions

- Voltage of battery: 8 V or more.
- Voltage of battery: 16.5 V or less.
- Engine speed: 650 r/min or more.
- Time since above engine condition: 1.5 seconds or more.
- Common high side 1 voltage: 7 V or more.
- Common high side 3 voltage: 7 V or more.
JUDGMENT CRITERIA

-





-





- Shift fork operation time: Shift fork operation time (threshold value) or more. (immediately)
- Shift fork operation time (threshold value): Equal the maximum allowed time x Coefficient. (immediately)

OBD-II DRIVE CYCLE PATTERN[ FUNCTIONAL CHECK - BLOCKED]

The shift fork operation time is threshold value or less.

LOGIC FLOW CHARTS (Monitor Sequence)[ Functional check - Neutral]





DTC SET CONDITIONS[ FUNCTIONAL CHECK - NEUTRAL]

Check Conditions

- Voltage of battery: 8 V or more.
- Voltage of battery: 16.5 V or less.
- Engine speed: 650 r/min or more.
- Time since above engine condition: 1.5 seconds or more.
- Shift fork 1 current gear: Neutral.
JUDGMENT CRITERIA

- Shift fork position: 1.8 mm (0.071 inch) or more. (250 millisecond)

OBD-II DRIVE CYCLE PATTERN[ FUNCTIONAL CHECK - NEUTRAL]

The shift fork position remains 1.8 mm (0.071 inch) or less for 250 millisecond.

LOGIC FLOW CHARTS (Monitor Sequence)[ Functional check - Shift fork 1 requested but shift fork 3 movement]





DTC SET CONDITIONS[ FUNCTIONAL CHECK - SHIFT FORK 1 REQUESTED BUT SHIFT FORK 3 MOVEMENT]

Check Conditions

- Voltage of battery: 8 V or more.
- Voltage of battery: 16.5 V or less.
- Engine speed: 650 r/min or more.
- Time since above engine condition: 1.5 seconds or more.
- Requested shift fork: Shift fork 1.
JUDGMENT CRITERIA

- Shift fork 3 position: -6 mm (-0.24 inch) [6th gear side] or more, or 1.8 mm (0.071 inch) [neutral position] or more, and initialized fork position - shift fork 1 position: 2.5 mm (0.098 inch) or less. (200 millisecond)

OBD-II DRIVE CYCLE PATTERN[ FUNCTIONAL CHECK - SHIFT FORK 1 REQUESTED BUT SHIFT FORK 3 MOVEMENT]

The status with the shift fork position -6 mm (-0.24 inch) [6th gear side] or less, or with 1.8 mm (0.071 inch) [neutral position] or less and with the initialized fork position - shift fork 1 position 2.5 mm (0.098 inch) or more continues for 200 millisecond.

LOGIC FLOW CHARTS (Monitor Sequence)[ Functional check - Shift fork 1 requested but shift fork 2 movement]





DTC SET CONDITIONS[ FUNCTIONAL CHECK - SHIFT FORK 1 REQUESTED BUT SHIFT FORK 2 MOVEMENT]

Check Conditions

- Voltage of battery: 8 V or more.
- Voltage of battery: 16.5 V or less.
- Engine speed: 650 r/min or more.
- Time since above engine condition: 1.5 seconds or more.
- Requested shift fork: Shift fork 1.
JUDGMENT CRITERIA

- Shift fork position: 6 mm (0.24 inch) [5th gear side] or less, or -6 mm (-0.24 inch) [3rd gear side] or more, or 1.8 mm (0.071 inch) [neutral position] or more, and initialized fork position - shift fork 1 position: 2.5 mm (0.098 inch) or less. (200 millisecond)

OBD-II DRIVE CYCLE PATTERN[ FUNCTIONAL CHECK - SHIFT FORK 1 REQUESTED BUT SHIFT FORK 2 MOVEMENT]

The status with the shift fork position 6 mm (0.24 inch) [5th gear side] or more, or with -6 mm (-0.24 inch) [3rd gear side] or less, or with 1.8 mm (0.071 inch) [neutral position] or less and with the initialized fork position - shift fork 1 position 2.5 mm (0.098 inch) or more continues for 200 millisecond.

PROBABLE CAUSES

- Malfunction of TC-SST-ECU
- Malfunction of TC-SST shift fork

DIAGNOSTIC PROCEDURE

Required Special Tools:

- MB991958 Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827 M.U.T.-III USB Cable
- MB991910 M.U.T.-III Main Harness A

STEP 1. Scan tool CAN bus diagnostics

Using scan tool MB991958, diagnose the CAN bus lines.

Q. Is the check result normal?

YES Go to Step 2.
NO Repair the CAN bus lines. CAN Bus Diagnostics Chart.) After repairing the CAN bus line, go to Step 2.
STEP 2. Monitoring unit No. check

(1)Check the freeze frame data (item No. 30 to No. 37).

(2)Check which monitoring unit (No. 160, No. 172, No. 182, or No. 183) is set.

Q. Which monitoring unit is set, No. 160, No. 172, No. 182, or No. 183?

No. 160 : Go to Step 4
Other than No. 160 : Go to Step 3
STEP 3. Check whether the DTC is reset.

(1)Erase the DTC.

(2)Drive with shifting to each gear range.

(3)Check that the DTC is reset.

Q. Is DTC No.P1836 set?

YES Replace the transaxle assembly. (Refer to Removal and Replacement.)
NO Intermittent malfunction. How to Cope With Intermittent Malfunctions.)
STEP 4. Check whether the DTC is reset.

(1)Erase the DTC.

(2)With the engine idle status, operate the shift lever in the following sequence: P -> R -> D -> R -> P. (Hold each range for 5 seconds or more.)

(3)Check that the DTC is reset.

Q. Is DTC No.P1836 set?

YES Replace the transaxle assembly. (Refer to Removal and Replacement.)
NO Intermittent malfunction. How to Cope With Intermittent Malfunctions.)