Shift Point Retard 2-3

Transmission Shift Point Retard 2-3 on Vehicles with Engines
102 and 103 with CAT


To enable the catalytic converter to more rapidly reach its operating temperature in the warm-up range, the 2 - 3 idle throttle upshift is retarded, i.e. this gearshift is performed slightly later.



Function Oil transmission shift point retard
The shiftover valve (Y3/2) is energized by the CIS-E control unit (N3) and the transmission shift point retard relay (K29).The governor pressure is lowered through a pressure oil line, which is bolted to the governor pressure test connection and to the connector, via a further oil line which is bolted into a hole on the transmission housing or into the centrifugal governor cover. Provided certain conditions are met (coolant temperature, vehicle speed and time), the solenoid valve is deenergized and the governor pressure is fully built up, the transmission shifts into 3rd gear.

Note:
Since February 1990 an CIS-E control unit is fitted to vehicles with engine 102 in which the transmission shift point retard operates only between a coolant temperature of 0 °C and 32 °C.


Vehicles with engine 103







O = Oil sump drain
MR = Governor pressure test connection
Y3/2 = Shift point retard switchover valve

Vehicles with engine 102








O = Oil sump drain
MR = Governor pressure test connection
Y3/2 = Shift point retard switchover valve