wow snooper diagnostic tool change governor speed

As with many modules, the TCM must often be initialized or programmed to fit the specific vehicle application. Due to modern powertrain technology becoming more complex, the separate TCM has been re-introduced in many applications and is often part of the automatic transmission valve body. Electronic automatic shift controls were added as ECMs became more sophisticated. Initially, the ECM was used to activate the torque converter clutch.

Adding planetary gear sets and hardware can increase the number of forward gear ratios.Ī voltage loss through the ignition switch can be detected by measuring the voltage drop between the underhood fuse box B+ terminal and any of the fuses activated by the ignition switch. The hardware used for holding a specific gear set in position usually consists of a friction band, multi-disc friction clutch or one-way mechanical roller clutch.

By holding the ring, planetary or sun gear in position, the planetary gear set can produce reduction, direct, overdrive, reverse and neutral gear ratios. The ring gear provides the outer gear set. As you might imagine, the sun gear is located at the center with the planetary gears revolving around it. Modern automatic transmissions contain multiple planetary gear sets composed of sun, planet and ring gears. The TCM monitors torque converter slippage and lock-up times by comparing the engine speed with the turbine shaft speed. A torque converter lock-up clutch is also standard equipment on modern vehicles. If the stator clutch fails, acceleration will become very sluggish due to poor torque multiplication. The stator is mounted on a one-way roller clutch that allows the stator to “free wheel” as fluid flow changes in both velocity and direction during deceleration. A stator is placed between the two halves to direct oil flow in a toroidal or spiraling motion through the converter during acceleration. The front half consists of an engine-driven impeller, while the back half consists of a turbine splined to the transmission input shaft. It’s no accident that the inside of a torque converter looks like a bagel cut in half. This screen displays the status of the various transmission shift solenoids.

Scan tools offer the best bet for diagnosing automatic transmission problems.

Wow snooper diagnostic tool change governor speed