How does TCM diagnose transmission shift solenoids?
The TCM activates them based upon inputs from both engine and transmission sensors. The diagnosis begins with a scanner and a DMM. A scanner identifies the faulty solenoid, or it’s a related circuit. If the scanner described a high power circuit code, check the solenoid’s ground side and follow the flow chart.
How is the solenoid of a transmission control module controlled?
On some transmissions (usually foreign) the solenoid is controlled by a 12 V signal from the (TCM) transmission control module. Other transmissions control the solenoid from the ground side, (usually domestic) by pulsing the ground circuit on and off.
What happens if you have a bad solenoid in your transmission?
Your transmission relies upon the positions of multiple solenoids to control the gear selection. If one or more solenoids are bad, you may lose the use of one or more gears, and may even be stuck in one particular gear or unable to shift into any gear at all. Do not confuse a slipping transmission with a solenoid problem.
Where are the solenoid plungers on a transmission?
Your transmission shift solenoids mount on the transmission valve body that controls fluid flow through the various circuits and passages in the transmission. The solenoid plungers are constantly bathed in fluid from the transmission, and metal salt from the manufacturing process and normal wear,…
What kind of transmission does the Honda Prelude have?
An innovative, new feature on the Prelude automatic transmission is Honda Sequential SportShift. It combines the ease and convenience of an automatic transmission with the shift-it-yourself fun of a manual. When the transmission shift lever is in the “D” mode, the transmission operates like any other Honda automatic transmission.
What does the lockup torque converter do on a Honda Prelude?
The lockup torque converter helps minimize fluid-coupling slippage by mechanically coupling the engine to the transmission during certain driving modes, such as steady-state cruising. The benefit is better mileage. The lockup feature works in 2nd and 3rd gears as well as 4th and also maintains lockup in 2nd, 3rd and 4th gears during deceleration.
What does centrifugal hydraulic cancellation do on Honda Prelude?
This is especially noticeable on full-throttle upshifts. A newly added centrifugal hydraulic cancellation mechanism improves shift control by minimizing centrifugal hydraulic pressure in the clutch packs. As a result, shifts are smoother, with less shift shock.
How does Grade Logic work in Honda Prelude?
Based on this, Grade Logic will determine that the Prelude is going uphill and it will determine how steep the grade is. It then chooses a shift map that will downshift and hold 3rd gear, thereby eliminating hunting between gears. Grade Logic also uses brake-pedal application as a control input.
The TCM activates them based upon inputs from both engine and transmission sensors. The diagnosis begins with a scanner and a DMM. A scanner identifies the faulty solenoid, or it’s a related circuit. If the scanner described a high power circuit code, check the solenoid’s ground side and follow the flow chart.
How is a shift solenoid in a transmission controlled?
These shift solenoids can be controlled by either the ground or the power side of the circuit. On some transmissions (usually foreign) the solenoid is controlled by a 12 V signal from the (TCM) transmission control module.
What to do if your transmission solenoid is not working?
If the scanner described a high power circuit code, check the solenoid’s ground side and follow the flow chart. If there’s a low power code, use the DMM to check the solenoid’s power feed. Automatic transmissions use two or three solenoids and turn them on and off at different times to achieve different gears.
Can a scanner lead to a faulty solenoid?
A scanner will lead to the faulty solenoid or it’s related circuit. If the scanner described a high power circuit code, check the ground side of the solenoid and follow the flow chart. If there’s a low power code, then use the DMM to check the power feed to the solenoid.