Cadillac Repair Questions? Ask a Mechanic for Answers ASAP
Have you tried starting the vehicle with the gear selector in neutral?
You can try unhooking battery for about 30 minutes to see if security will reset.
If you still have access to the scan tool (w/ factory options) you could reset the TDM and that would bring it out of security lockout. There is one other possible way also, if you want to accept the call I can walk you through it.
That U0140 is usually a short inside the BCM which means it needs to be checked at the dealership and possibly replaced.
The only other thing you can try is to unhook battery overnight and see if it resets. Please remember to rate my service and accept the answer (its the only way I get compensated).
TSB Number: 08-07-30-021 NHTSA Number: 10025402 TSB Date: April 1, 2008 Date Added to File: August 6, 2008Failing Component: Engine And Engine Cooling: EngineSummary: Loss of high speed gm lan communications, intermittent no crank, ipc gauge fluctuation, intermittent door lock cycling, transmission may not shift, DTCs U0073, U0100, U0101, U0102, U0140 (repair backed out terminal in transmission harness connections).
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