P181C

DTC P181C: Clutch 1 (Pressure high range out)

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 clutch 1 pressure is normal.

DESCRIPTIONS OF MONITOR METHODS
The pressure of the clutch 1 is too high.

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)
^ P0841: Clutch 1 pressure sensor system (Poor performance)
^ P0842: Clutch 1 pressure sensor system (Output low range out)
^ P0843: Clutch 1 pressure sensor system (Output high range out)
^ P1836: Shift fork 1 malfunction
^ P183D: Shift fork 2 malfunction

Sensor (The sensor below is determined to be normal)
^ Clutch 1 pressure sensor

LOGIC FLOW CHARTS (Monitor Sequence) [Target clutch 1 (odd) pressure: 3,000 hPa or more]

Example of the time required
i) When the shift lever position is P. The time required is always 220 msec.
ii) When the shift lever position is " R -> N":
If the transmission fluid temperature is -10°C (14°F) or more, the time required is 1,220 msec.
If the transmission fluid temperature is lower than -10°C (14°F), the time required is 2,220 msec.
iii) When shift lever position is D:
If the transmission fluid temperature is -10°C (14°F) or less, the time required is 3,220 msec.
If the transmission fluid temperature is higher than -10°C (14°F), the time required is 2,220 msec.

DTC SET CONDITIONS [TARGET CLUTCH 1 (ODD) PRESSURE: 3,000 HPA OR MORE]

Check Conditions
^ Engine speed: 650 r/min or more.
^ Time since above engine condition: 1.5 seconds or more.
^ Clutch 1 (odd) state: Slip or engaged.
^ Target clutch 1 (odd) pressure: 3,000 hPa or more.

JUDGMENT CRITERIA
^ Calculated pressure: -5,000 hPa or less. (Time required*)

Example of the time required
i) When the shift lever position is P. The time required is always 220 msec.
ii) When the shift lever position is "R->N":
If the transmission fluid temperature is -10°C (14°F) or more, the time required is 1,220 msec.
If the transmission fluid temperature is lower than -10°C (14°F), the time required is 2,220 msec.
iii) When shift lever position is D:
If the transmission fluid temperature is -10°C (14°F) or less, the time required is 3,220 msec.
If the transmission fluid temperature is higher than -10°C (14°F), the time required is 2,220 msec.

LOGIC FLOW CHARTS (Monitor Sequence) [Target clutch 1 (odd) pressure: 1,400 hPa or more to 3,000 hPa or less]

Example of the time required
i) When the shift lever position is P: The time required is always 220 msec.
ii) When the shift lever position is "R->N":
If the transmission fluid temperature is -10°C (14°F) or more, the time required is 1,220 msec.
If the transmission fluid temperature is lower than -10°C (14°F), the time required is 2,220 msec.
iii) When shift lever position is D:
If the transmission fluid temperature is -10°C (14°F) or less, the time required is 3,220 msec.
If the transmission fluid temperature is higher than -10°C (14°F), the time required is 2,220 msec.

DTC SET CONDITIONS [TARGET CLUTCH 1 (ODD) PRESSURE: 1,400 HPA OR MORE TO 3,000 HPA OR LESS]

Check Conditions
^ Engine speed: 650 r/min or more.
^ Time since above engine condition: 1.5 seconds or more.
^ Clutch 1 (odd) state: Slip or engaged.
^ Target clutch 1 (odd) pressure: 1,400 hPa or more.

JUDGMENT CRITERIA
^ Calculated pressure: -2,000 hPa or less. (Time required*)

Example of the time required
i) When the shift lever position is P: The time required is always 220 msec.
ii) When the shift lever position is " R->N ":
If the transmission fluid temperature is -10°C (14°F) or more, the time required is 1,220 msec.
If the transmission fluid temperature is lower than -10°C (14°F) the time required is 2,220 msec.
iii) When shift lever position is D:
If the transmission fluid temperature is -10°C (14°F) or less, the time required is 3,220 msec.
If the transmission fluid temperature is higher than -10°C (14°F) the time required is 2,220 msec.

DTC SET CONDITIONS [TARGET CLUTCH 1 (ODD) PRESSURE: 1,400 HPA OR LESS]

Check Conditions
^ Engine speed: 650 r/min or more.
^ Time since above engine condition: 1.5 seconds or more.
^ Clutch 1 (odd) state: Slip or engaged.
^ Target clutch 1 (odd) pressure: 1,400 hPa or less.

JUDGMENT CRITERIA
^ Calculated pressure: -1,000 hPa or less. (Time required*)

Example of the time required
i) When the shift lever position is P: The time required is always 220 msec.
ii) When the shift lever position is "R->N":
If the transmission fluid temperature is -10°C (14°F) or more, the time required is 1,220 msec.
If the transmission fluid temperature is lower than -10°C (14°F), the time required is 2,220 msec.
iii) When shift lever position is D:
If the transmission fluid temperature is -10°C (14°F) or less, the time required is 3,220 msec.
If the transmission fluid temperature is higher than -10°C (14°F), the time required is 2,220 msec.

PROBABLE CAUSES
^ Malfunction of TC-SST-ECU

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. After repairing the CAN bus line, go to Step 2.

STEP 2. Check whether the DTC is reset.
After the test run, check that the DTC is reset.
Q: Is DTC No. P181C set?
YES: Replace the mechatronic assembly.
NO: Intermittent malfunction.