Posted by John Forward on April 11, 2012, 10:09 am
Year of Manufacture *: 2004 ( Optional ) Engine Code or CC: 0.6 M160 E6AL
Car arrived stuck in Reverse gear with the 3 bars showing on the change display & non start. Code read with Launch: P202B Gear shift operation had be repeated P202F The transmission is jammed. Faults cleared, display now shows R. Any attempt to change out of R causes the 3 bars to return (and the fault codes) Removed the gear change motor and manually revolved the selector drum to neutral, cleared faults and display now shows N and engine can be started. Any attempt at selecting forward gears causes the 3 bars again and no gear selected. R can be selected and works correctly, selecting neutral brings up the 3 bars (and fault codes). So far I have checked: The gear change motor, works fine in both directions with plenty of power, speed sensors in the motor are connected but haven’t checked their output running. Gear angle sensor (mounted on the end of the selector drum) replaced. Clutch actuator, cleaned out crud and lubricated, adjusted position. Clutch disengages ok with no drag. Wiring to gearbox, no broken wires or damaged insulation. Gearbox, forward gears are working if the selector drum is turned. I have found someone with a Star machine to diagnose again in case anything not reported by the Launch but not till the weekend. I understand the Star can teach the gear positions again maybe this is the answer ? Any help most great fully received as now pulling my hair out. Yours, John F
Hi John We have re programed these to fix shift faults. wait for tech with star to turn up.Pretty sure you are not supposed to remove motor without setting up with star first?? Merc say a nightmare to set up ?? if motor removed without setting in star first. Regards peter
An update & futher request for help. A colleague code read with the Star system and reported the same fault codes as the Launch. On further testing there appeared to be a difference between two reference values the ECU was looking at for gear position. We tried the re-teach gear position adaption but the procedure failed every time. Does anyone have a written procedure you are supposed to follow ? Star system gave no extra info. on how to manually set up the gearbox then input the values from the sensors into the software. Many thanks John F