Solenoid S1 and S2
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The solenoids S1 and S2 are located in the transmission control system, which is fitted on the front edge of the transmission. The solenoids are the on/off type and consist of an electrical coil that controls a hydraulic valve. The solenoids are supplied 12 V via the transmission control module (TCM) and are grounded in the control system. The solenoids control shifting and the transmission control module (TCM) activates the solenoids with engine braking for 1st gear.
The solenoids can be diagnosed.