P0121

Diagnostic Trouble Codes 00518 / P0121 - 5 Spd. Automatic Transmission 01V

DTC 00518 / P0121 for vehicles with CAN-Bus A)





1) Pay attention to which hydraulic control the transmission has when selecting measuring value block.
A) There is a difference between vehicles with and without CAN-bus.

Note for DTC 00518 / P0121, vehicles with CAN-Bus A):

^ The signal from the TP sensor -G39- is transmitted by the engine control module to the transmission control module via the CAN-bus.
^ Requirements for malfunction recognition- Malfunction of the component is recognized by the Engine Control Module. This diagnosis is transmitted to the Transmission Control Module (TCM) via the CAN-bus wiring.

DTC 00518 / P0121 vehicles without CAN-Bus A)





1) One of these indications is also displayed for the applicable component.
2) On vehicle with Motronic fuel injection and ignition, the only malfunction that will be displayed is "Wrong signal".
3) Pay attention to which hydraulic control the transmission has when selecting measuring value block.
A) There is a difference between vehicles with and without CAN-bus.

Note for DTC 00518 / P0121, vehicle types without CAN-Bus A):

^ The signal is transmitted in digital form from the Throttle Position (TP) sensor -G69- via the Engine Control Module (ECM) to the Transmission Control Module (TCM).
^ Malfunction recognition of DTC 00518 by the TCM is much more sensitive than detection by the ECM. This means that a brief interruption in the throttle position signal (up to 1 second) is not detected by the ECM, but is registered as a malfunction by the TCM.
^ Requirements for malfunction recognition - frequency of digital signal to TCM is outside the permissible tolerance (signal pulse must occur at least every 30 ms).