Case IH 2669 (6157.11) - DEC – Transmission Control Unit (TCU): Synchro 6 Solenoid - Generic Error

Typically indicates an electrical fault (such as an open circuit, a short to 12V, a short to ground) or a mechanical failure where the synchronizer fails to engage or is no longer engaged when commanded.

• MAXXUM T4E

1. 1

   Swap the suspect Synchro 6 solenoid with another known-good synchro solenoid on the transmission valve block (e.g., Synchro 4 or 5). If the fault code changes to match the new location, the solenoid is faulty.

2. 2

   Test the signal voltage of the synchro position sensor and compare it to a known-good sensor (like the forward/reverse sensor).

3. 3

   Remove the transmission top plate and run the tractor to visually verify if the shift forks are physically moving when commanded.

1. 1

   Perform transmission calibration

   Any time a synchro solenoid or position sensor is replaced on a Case IH transmission, a transmission calibration must be performed via the tractor's display monitor.