Action Taken

WARNING: This page is about a different car, the 1990 Cadillac Fleetwood and 1990 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.

ECM turns on SERVICE SOON light.
Enable fuel injection on future ignition cycles without regard for Pass Key Fuel Enable Input status.

Code E58 is an indication that Pass Key Fuel Enable Input has failed after a good signal was received in a given engine run cycle. Pass Key system enables engine operation by:

Allowing starter motor to engage.
Issuing a Fuel Enable signal to ECM.

Once engine is running, ECM continuously monitors Fuel Enable signal, testing for a circuit or Pass Key module failure that would prohibit a positive fuel enable on future ignition cycles. ECM will not cancel fuel injection after it has been approved within a given ignition cycle. Therefore, a stalling condition cannot be caused by Pass Key system failures.

NOTE: Test numbers refer to test numbers on diagnostic chart.

Test Number 1) If engine will crank, problem has been isolated to Pass Key Module, ECM or Fuel Enable circuit. If engine will not crank, problem is in Pass Key System.

Test Number 2) Checking voltage input to ECM will identify if ECM is at fault. Typical signal will be approximately 2.5 volts.

Test Number 3) Voltage is too low - could be faulty Pass Key Module, a poor connection at ECM or a short to ground in Fuel Enable circuit.

Test Number 4) Voltage is too high - could be faulty Pass Key Module, a poor connection at Pass Key Module or a short to voltage or an open in Fuel Enable circuit.