Lock-up control solenoid

The recovery stragegy involves the deactivation of all the solenoids, so no automatic gear changes are ef-fected, the torque converter is not locked and the hydraulic pressure is not varied.

The vehicle can travel because each position of the selector lever corresponds to the engagement of a par-ticular transmission ratio, by the movement of the hydraulic distributor.

Lock-up control solenoid

In the case of error, the torque converter locking function is disabled.

Coolant temperature sensor

In the case of error, a substitutive value of 75°C is assigned.

Kick-down switch

In the case of error, it is considered ON if the throttle valve aperture is greater than 73.5%, OFF if it less than 70%.

GEAR CHANGE SOLENOIDS

The gear change solenoids S1 (A) and S2 (B) are located at the front of the gearbox and they manage the gear changes. The solenoids are actually normally closed (N.C.) electrovalves which, receiving a signal from the control module, change their position to allow the engagement of the different trans-mission ratios, in accordance with the fol-lowing table.

Gearbox sensors/actuators connector (view of contact side)

The resistance of the gear change solenoids S1 and S2 can be measured by disconnect-ing the connector and connecting an ohm-meter as shown in the figure.

Resistence: 13 ± 2 ohm at 20°C