Test Procedure
The auto gear box control unit is able to store freeze frame data-like information. It stores 3 parameters (variables) during the first occurrence of a fault code. These parameters are not refreshed if the fault code reoccurs. Land Rover Testbook/T4 scan tool is able to retrieve these variables. After retrieving the stored variables, they must be multiplied by appropriate conversion factors in order to obtain the freeze frame data value. See Fig 1. Each fault code will have a set of 3 variables assigned to it. Use the conversion table to obtain the proper freeze frame data value. See Fig 1.
When a fault code diagnostic test indicates that the auto gear box control unit is faulty or other transmission electrical device is faulty, check the entire electrical circuit associated with that device before replacing it. See WIRING DIAGRAMS . When diagnosing a transmission problem, suspect electrical failure before suspecting mechanical failure.