What is a Subaru automatic transmission reference ring?
The reference ring, also known as the timing ring, is a toothed disc attached to the transmission shaft in the automatic transmission (AT) of Subaru vehicles.
Purpose of automatic transmission reference ring
The reference ring is used to determine the position of the gearbox shaft and the gear currently engaged. The teeth on the reference ring are sensed by the output shaft speed sensor, which relays the information to the transmission control module (TCM). The TCM uses this information to control gear shifting, ignition timing, and other functions.
Problems and symptoms of the Subaru automatic transmission reference ring
A damaged or misaligned reference ring can lead to a variety of automatic transmission problems, including:
* Problems with gear shifting
*Stuck in gear
* Gear slippage
*Transmission related fault codes
* Limp mode (emergency mode)
Causes of damage or displacement of the reference ring of a Subaru automatic transmission
*Low transmission fluid level
* Worn or broken gearbox bearings
* Impact or collision
* Incorrect installation of the reference ring
Diagnostics and repair of reference ring of Subaru automatic transmission
Diagnosis of the reference ring usually includes:
* Read trouble codes using OBD-II scanner
* Visual inspection of the reference ring
*Checking the transmission fluid level
* Listening to noise and behavior of the gearbox
If diagnostics confirm that the reference ring is causing the problem, the transmission must be removed and the reference ring replaced. The reference ring should be replaced by a qualified technician.
Consequences of untimely repairs
If a faulty or misaligned reference ring is not repaired promptly, it can result in further damage to the transmission, costly repairs, or even the need for replacement.