Code 65, Injector Current Low: Notes

PCM has 2 injector driver circuits, each controlling a pair of injectors (1 and 4, or 2 and 3). PCM monitors current of each injector driver circuit by measuring voltage drop through a fixed resistor. PCM is able to control voltage drop. Current through each driver is allowed to rise to peak of 4 amps, enabling injectors to open quickly; current is then reduced to one amp, holding injectors open. This is called "peak and hold". If current cannot reach a 4-amp peak, Code 65 is set. This code is also set if:

• 4-amp injector current was not reached on each circuit.
• Battery voltage greater than 9 volts.
• Injectors pulsed on longer than calibrated pulse width.
• Conditions met for 20 seconds.
  NOTE: Test numbers refer to numbers on diagnostic chart.

1. Determines if conditions for code are hard or intermittent.
2. Checks PCM and harness wiring to 3-terminal injector harness connector.
3. This tests for open injector harness or injector.
4. Results of step 2) will determine which branch to follow on Code 65 (2 of 2) flow chart.
5. Each harness was confirmed as being okay in step 2). This test will check remainder of circuit from injectors to PCM.
6. This checks for short to voltage in injector driver circuits.
7. Determines if injector driver circuits are shorted to ground.