Case Studies 05

Vehicle Details

• Model: Ford EcoSport
• Year: 2014
• Engine: 1.5L Petrol
• Transmission: DPS6 / 6DCT250 Dual-Clutch Automatic
• Odometer: ~4,000 km
• Condition: Vehicle unused for approximately 2 years

1. Customer Complaint

The customer reported the following issues:

• Erratic and jerky gear shifts
• Improper engagement of certain gears
• Transmission warning indicator illuminating intermittently
• Overall poor drivability

2. Initial Scan & Fault Codes

Using Launch X431 and Bosch ESItronic (KTS 570), the following fault codes were retrieved:

• P07A5 – Transmission Friction Element “B” Stuck On
• P0884 – TCM Power Input Signal Intermittent

These codes indicated a likely issue with Clutch B (even gears: 2, 4, 6) in the DPS6 transmission.

3. Technical Background (DPS6 Transmission)

The DPS6 is a dry dual-clutch transmission consisting of:

• Two independent clutches:
  • Clutch A → odd gears (1, 3, 5)
  • Clutch B → even gears (2, 4, 6 + reverse)
• Electro-mechanical clutch actuators
• Input shaft speed sensors used by the TCM for clutch control and synchronization

Extended vehicle inactivity often leads to:

• Rust formation on clutch components
• Sticking of pressure plates
• Degraded sensor performance

4. Mechanical Inspection & Repair

Based on the fault codes and symptoms:

• The complete transmission assembly was removed
• Internal inspection revealed deterioration consistent with long-term non-use
• The entire dual-clutch assembly was replaced with a new unit:
  • LUK Dual Clutch Kit – Part No. 6020008000

After reassembly:

• Proper clutch unlocking was performed
• Transmission was refitted to the engine
• Clutch adaptation procedure was carried out using the diagnostic scanner

5. Initial Road Test After Clutch Replacement

• Vehicle driven for approximately 45 km
• Gear shifting was smooth
• No clutch-related fault codes were present initially

However, near the end of the test drive:

• Transmission warning indicator reappeared intermittently
• Vehicle motion became erratic under certain conditions

6. Secondary Diagnosis – Sensor-Related Faults

A fresh scan revealed new fault codes:

• P2765 – Input Shaft Speed Sensor B Circuit Fault
• P2767 / P2768 – Input Shaft Speed Sensor B Intermittent Signal

This indicated an issue not with the clutch, but with input shaft speed sensing, which is critical for TCM clutch control.

7. Sensor Testing & Technical Findings

The DPS6 uses 2-wire active input shaft speed sensors, not conventional passive VR sensors.

Key findings:

• Sensor A (short, grey) showed ~1.2 MΩ → internal open circuit
• Sensor B (long, black) showed ~300 Ω, but failed intermittently under heat/load

Further testing revealed:

• These sensors are active, externally excited magneto-resistive sensors
• Resistance testing alone is unreliable
• Ford service manuals therefore rely on voltage supply, continuity, and live data checks rather than resistance specifications

8. Corrective Action – Sensor Replacement

As a preventive and corrective measure:

• Both input shaft speed sensors (A & B) were replaced with new OE-spec units
• Wiring and connectors were inspected and verified
• TCM fault codes cleared
• Live data confirmed stable RPM signals from both sensors

9. Final Testing & Validation

• Vehicle driven for an additional 80 km under mixed driving conditions
• Total post-repair testing distance: ~125 km
• Results:
  • Smooth gear shifts across all gears
  • No warning indicators
  • No fault codes stored or pending
  • Stable data stream values from TCM

10. Final Conclusion

This case required a two-stage resolution:

1. Mechanical repair
   • Replacement of degraded dual-clutch assembly (P07A5)
2. Electronic diagnosis & repair
   • Identification and replacement of failing input shaft speed sensors (P2765 / P2767 / P2768)

The vehicle now operates normally with restored drivability and no transmission-related faults.

11. Key Takeaways

• Long periods of vehicle inactivity can cause both mechanical and electronic failures
• DPS6 issues are often multi-layered, requiring structured diagnosis
• Input shaft speed sensors in DPS6 are active sensors, not traditional VR types
• Blind part replacement without understanding sensor behavior can lead to misdiagnosis