Toggle Side Panel

Shopping Cart

No products in the basket.

Shopping Cart

No products in the basket.

Close search
Home / DTC / P1908 — Gearbox shift drum error

P1908 — Gearbox shift drum error

Detailed page for trouble code P1908.

34,405codes
59brands
11,914generic
22,491specific
All codes P-codes (Powertrain) B-codes (Body) C-codes (Chassis) U-codes (Network/User) Tesla Alerts
Reset
Code

P1908

MITSUBISHI P — Powertrain

Gearbox shift drum error

Brand: MITSUBISHI
Type: P — Powertrain
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Faulty shift drum position sensor (Hall, magnetic pickup or switch)
  • Damaged wiring or poor connector connection to the sensor/actuator
  • Faulty shift actuator/motor or solenoid that drives the drum
  • Mechanical wear, binding or broken components in the shift drum/selector assembly
  • Incorrect shift drum position calibration or ECU software fault
  • Low or contaminated transmission fluid (where applicable) causing mechanical drag

Symptoms

  • Transmission unable to select gears normally or erratic shifting
  • Gearbox stuck in a single gear, limp/limitation mode or failsafe mode
  • Check Engine / transmission warning lamp illuminated
  • Unusual noise when attempting to change gears
  • Inability to engage some gears or rough/slow gear engagement

What to check

  • Read and record all stored DTCs and freeze frame data with a capable scan tool
  • Visual inspection of transmission shift drum area for physical damage, foreign objects or wear
  • Inspect sensor and actuator connectors for corrosion, bent pins, damaged seals and secure fit
  • Check wiring harness along its length for chafing, breaks, or heat damage
  • Check transmission fluid level and condition if applicable
  • Attempt to reproduce the fault while capturing live data (shift drum position, commanded position, actuator output)

Signal parameters

  • Position sensor type: typically Hall-effect (digital 0–5 V) or magnetic pickup (AC waveform); expect a clean square or sinusoidal signal that changes with drum rotation
  • Reference supply to sensor: usually 5 V reference from ECU (verify present and stable)
  • Ground: solid chassis/ECU ground; low resistance to ground expected
  • Actuator drive: switched 12 V or PWM command from ECU when moving drum; measure duty cycle/voltage while commanding shift
  • When stationary in a known gear the sensor output should match the stored/expected position value (compare to manufacturer live-data values)

Diagnostic algorithm

  1. Connect a diagnostic scan tool, read DTCs and live data. Note freeze frame and any other transmission codes.
  2. Clear the code and perform a controlled test to reproduce P1908 while monitoring live data: observe commanded drum position vs actual position and actuator commands.
  3. Perform visual inspection: connectors, wiring harness, shift drum area and actuator for obvious damage, corrosion or mechanical interference.
  4. Back-probe the sensor connector: verify reference voltage (typically 5 V), signal voltage (changes with drum movement) and ground continuity. Repair any open/short circuits.
  5. If sensor is a magnetic pickup, use an oscilloscope or meter to verify AC waveform while rotating drum. If Hall sensor, verify square wave or switching between ~0–5 V.
  6. Command the shift actuator from the scan tool (if supported) and observe movement and current/voltage. If actuator does not move while commanded, check supply and ground and measure coil resistance if applicable.
  7. Inspect mechanical operation: manually rotate or move selector mechanism (with engine off and safe procedures) to check for binding, worn detents, broken teeth or foreign objects preventing full travel.
  8. Check for correct transmission fluid level and condition; low/contaminated fluid can impede actuator/drum movement in some designs.
  9. If electrical tests pass and mechanical is OK, perform the manufacturer-recommended shift drum/selector calibration or relearn procedure using the scan tool, then retest.
  10. If fault persists after wiring, sensor and actuator checks, consider replacing the sensor or actuator assembly and reverify. If replacement does not correct the issue, inspect internal gearbox components and consider professional gearbox inspection/repair.

Likely causes

  • Open/short in sensor supply, signal, or ground circuit
  • Intermittent connector corrosion at the sensor or ECU connector
  • Failed Hall-effect sensor or pickup on the shift drum
  • Shift actuator not moving drum to commanded position (electrical or mechanical failure)
  • Shift drum teeth or detent wear allowing incorrect position feedback

Fault status

⚠️ Status
Gearbox shift drum position/feedback error — sensor or actuator circuit out of expected range or mechanical position mismatch detected.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-3.0 hours
406

Browse 406 MITSUBISHI manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

MITSUBISHI

Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email

Report

Harassment or bullying behavior
Contains mature or sensitive content
Contains misleading or false information
Contains abusive or derogatory content
Contains spam, fake content or potential malware

Block Member?

Please confirm you want to block this member.

You will no longer be able to:

  • See blocked member's posts
  • Mention this member in posts
  • Invite this member to groups
  • Message this member
  • Add this member as a connection

Please note: This action will also remove this member from your connections and send a report to the site admin. Please allow a few minutes for this process to complete.

Report

You have already reported this .