Diagnostic Trouble Code (DTC) Information

DTC information
998 8686 Replaced by 9511532 998 8686 Replaced By 9511532
Condition




Shift solenoids S2 and S1 operate in tandem to control gear-shifting. Solenoid S2 operates when it receives battery voltage from the transmission control module (TCM) and is activated in reverse, 1st and 2nd gears. Diagnostic trouble code (DTC) AT-221 is posted if the transmission control module (TCM) registers a short-circuit to ground in solenoid S2 circuit when the solenoid should not be activated. Solenoid S2 cannot be activated.

Substitute value
The transmission control module (TCM) limp-home program has been initiated.

Possible source
- Short-circuit to ground in signal cable.
- Defective solenoid

Fault symptom[s]
- The combined instrument panel warning lamp flashes.
- Deterioration in performance because the transmission control module (TCM) prevents activation of the solenoids, this stops gear-shifting. The transmission operates only in 3rd gear in positions 3 and L, 4th gear in position D and reverse in position R. Shifting can only be carried out manually between 3rd, 4th, and reverse gear.
- No system pressure solenoid STH control resulting in constant maximum system pressure leading to harsher shifting and gear meshing.
- No lock-up function.

Note! The Motronic 4.4 engine control module (ECM) posts a diagnostic trouble code (DTC) when the transmission sends a malfunction indicator lamp (MIL) request. Erase this diagnostic trouble code (DTC) in the Motronic engine control module (ECM) when the transmission fault has been repaired.