General information (Peugeot 106)

Some models covered in this manual have an electronically controlled three-speed fully-automatic transmission, consisting of a torque converter, an epicyclic geartrain and electro-hydraulically-operated clutches and brakes.

The torque converter provides a fluid coupling between engine and transmission, which acts as an automatic clutch and also provides a degree of torque multiplication when accelerating.

The epicyclic geartrain provides either of the three forward or one reverse gear ratios, according to which of its component parts are held stationary or allowed to turn. The components of the geartrain are held or released by brakes and clutches which are activated hydraulically according to signals from the transmission electronic control unit (ECU). A fluid pump within the transmission provides the necessary hydraulic pressure to operate the brakes and clutches.

Automatic operation of the transmission is controlled by an electronic control unit which receives signals on vehicle operating conditions from various sensors. The sensors typically provide information on vehicle speed, selector lever position, throttle position and engine speed, enabling the ECU to select the appropriate gear ratio and gear change point.

Driver control of the transmission is by a six-position selector lever. The transmission has a "drive" position and a "hold" facility on the first two gear ratios. The "drive" position "D" provides automatic changing throughout the range of all three gear ratios and is the one to select for normal driving. An automatic kickdown facility shifts the transmission down a gear if the accelerator pedal is fully depressed. The "hold" facility is very similar, but limits the number of gear ratios available -ie when the selector lever is in the "2" position, only the first two ratios can be selected; in the "1" position, only first can be selected. The "hold" facility is useful for providing engine braking when travelling down steep gradients, or for preventing unwanted selection of top gear on twisty roads. Note, however, that the transmission should never be shifted down a position if the engine speed exceeds 4000 rpm.

Due to the complexity of the automatic transmission, any repair or overhaul work must be left to a Peugeot dealer with the necessary special equipment for fault diagnosis and repair. The contents of the following Sections are therefore confined to supplying general information and any service information and instructions that can be used by the owner.