N-D Change With Pitch Control (Squat); Inhibition Of Reverse Gear; Self-Test; Error Detection Conditions - Fiat Bravo Service Manual

Auto transmission and differential
Components and operation
21-27.

N-D change with pitch control (squat)

When the selector lever is moved from position N to position D, the control module temporarily engages
2nd gear, and thenn changes to 1 st gear. In this way the jolt caused by the engagement of 1 st gear and the
resulting pitching movement of the vehicle are reduced.

Inhibition of reverse gear

With the selector lever at position R, with a vehicle speed of over 7 km/h, the control module sends a sig-
nal to the gear change solenoids (solenoid 1 not activated -OFF- and solenoid 2 activated -ON-) inhibit-
ing reverse gear.
The inhibition of reverse is deactivated in the following cases:
- vehicle speed below 5 km/h;
- selector lever position other than R.

Self-test

The electronic control system constantly monitors the sensors, control solenoids and all the other elec-
tronic components, in order to detect faults and malfunctions immediately; these errors are memorized in
the control module and can be read using the FIAT/LANCIA Tester.

Error detection conditions

The control module can detect errors in the various components only under particular conditions. W i t h
the ignition set to ON or START, and in all other conditions, the following errors can be detected:
- error in gear change solenoid S 1 ;
- error in gear change solenoid S2;
- error in lock-up clutch control solenoid SL;
- error in pressure control solenoid STH;
- error in selector lever position sensor;
- error in throttle position sensor;
- error in kick-down switch;
- error checking transmission of driving torque reduction signal;
- error in gearbox oil temperature sensor when it still indicates an oil temperature of below 10°C after
the engine coolant has reached 75°C.
With the engine running, the f o l l o w i n g are detected:
- error in battery voltage;
- error in coolant temperature sensor after a period of 10 minutes.
2 4
Bravo-Brava
This function only intervenes if the following c o n d i -
tions arise simultaneously:
- brake pedal pressed (stop lights o n ) ;
- throttle valve closed (throttle aperture 0%);
- vehicle speed below 7 k m / h ;
- driving mode is N O R M A L or SPORT;
- when the selector lever is moved from position
N to position D.
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Publication no. 506.670/06