Part 1
DTC P1770 (P0705): Transmission Range Switch System (Open Circuit)
CAUTION:
If DTC P1770 (P0705) has been set, TCL related DTC C1397 is also set. After DTC P1770 (P0705) has been diagnosed, don't forget to erase DTC C1397.
CIRCUIT OPERATION
- Battery positive voltage is applied to the transmission range switch (terminal 8) when the ignition switch is turned "ON."
- Battery positive voltage is applied to the PCM (terminal 67) when the transmission range is in the "P" range. The PCM judges that the transmission range is in the "P" range when the battery positive voltage is applied.
- Battery positive voltage is applied to the PCM terminal 61 (77, 73) when the selector lever is in the "R" range ("N," "D" range). The PCM judges that the selector lever is in the "R" range ("N," "D" range) when the battery positive voltage is applied.
DESCRIPTIONS OF MONITOR METHODS
- If no signal is input from transmission range switch for more than 30 seconds, PCM judges that transmission range switch has a failure.
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)
- Not applicable
Sensor (The sensor below is determined to be normal)
- Not applicable
LOGIC FLOW CHARTS (Monitor Sequence)
DTC SET CONDITIONS
Check Conditions, Judgment Criteria
- Transmission range switch: no signal detected. (30 seconds)
OBD-II DRIVE CYCLE PATTERN
Start the engine, keep the vehicle stopped in "P," "R," "N," "D" ranges respectively for more than one minute, and turn "LOCK" (OFF) the ignition switch. Then restart the engine, and stop the vehicle in "P," "R," "N," "D" ranges respectively for more than one minute.
TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CODE TO BE SET ARE:)
- Malfunction of the transmission range switch
- Malfunction of the ignition switch
- Damaged harness or connector
- Malfunction of the PCM
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A
STEP 1. Using scan tool MB991958, check data list item 34: Transmission Range Switch.
(1)
CAUTION:
To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
Connect scan tool MB991958 to the data link connector.
(2)Turn the ignition switch to "ON" position.
(3)Set scan tool MB991958 to the data reading mode.
- Item 34: Transmission Range Switch.
- Move the selector lever to "P," "R," "N," "D" and sport mode positions and confirm that the selected transmission range match the positions shown on scan tool MB991958. (The scan tool displays "D" range when the selector lever is shifted to the sport mode).
(4)Turn the ignition switch to the "LOCK" (OFF) position.
Q. Does the scan tool indication correspond to the actual transmission range?
YES It can be assumed that this malfunction is intermittent. How to Cope With Intermittent Malfunctions.
NO (no correct transmission range is displayed) : Go to Step 2.
NO (Only "P" position is not displayed correctly) : Go to Step 6.
NO (Only "R" position is not displayed correctly) : Go to Step 12.
NO (Only "N" position is not displayed correctly) : Go to Step 17.
NO (Only "D" position is not displayed correctly) : Go to Step 22.
NO [Only sport mode position is not displayed correctly ("D" is not displayed.)] : Go to Step 29.
STEP 2. Check the transmission range switch.
Measure the resistance between the terminals for each transmission range as indicated in the table below.
NOTE:
For vehicles with sport mode, four positions (P, R, N, D) are used.
Q. Does the resistance measure less than 2 ohms for each transmission range?
YES Go to Step 3.
NO Replace the transmission range switch. Transaxle Disassembly and Assembly Transaxle [4A/T] or Transaxle [5A/T].
STEP 3. Check intermediate connector A-15, C-24, transmission range switch connector B-113, joint connector (1) C-28 and junction block connector C-203 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q. Are the connectors and terminals in good condition?
YES Go to Step 4.
NO Repair or replace the damaged components. Harness Connector Inspection.
STEP 4. Check harness for open or short circuit to ground between transmission range switch connector B-113 terminal 8 and junction block connector C-203 terminal 12.
Q. Is the harness wire in good condition?
YES Go to Step 5.
NO Repair or replace the harness wire.
STEP 5. Using scan tool MB991958, check data list item 34:Transmission Range Switch.
(1)
CAUTION:
To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
Connect scan tool MB991958 to the data link connector.
(2)Turn the ignition switch to "ON" position.
(3)Set scan tool MB991958 to the data reading mode.
- Item 34: Transmission Range Switch.
- Move the selector lever to "P," "R," "N," "D" and sport mode positions and confirm that the selected transmission range match the positions shown on scan tool MB991958. (The scan tool displays "D" range when the selector lever is shifted to the sport mode).
(4)Turn the ignition switch to the "LOCK" (OFF) position.
Q. Is the switch operating properly?
YES It can be assumed that this malfunction is intermittent. How to Cope With Intermittent Malfunctions.
NO Replace the PCM. When the PCM is replaced, register the encrypted code. Encrypted Code Registration Criteria Table.