Powertrain Controls - ECM/PCM

DTC 35 Injection Pulse Width Error (Response Time Short):

Injection Pulse Width:

CIRCUIT DESCRIPTION
The fuel injection driver receives an inject command signal from the Powertrain Control Module (PCM) and provides a current regulated output to the fuel solenoid that controls injection. It also returns an injection pulse width signal back to the PCM to inform it when the fuel solenoid has actually seated. This injection pulse width signal is measured in micro seconds.

DTC 36 WILL SET WHEN
^ Battery voltage greater than 10 volts.
^ Coolant temperature greater than 20°C (68°F).
^ Injection pulse width greater than 2.5 milliseconds.

ACTION TAKEN (PCM will default to)
Fixed injection pulse width value of 1.95 milliseconds.

DTC 36 WILL CLEAR WHEN
The fault condition(s) no longer exist, and the ignition switch is cycled "OFF" then "ON."

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This step checks the fuel solenoid driver ignition feed circuit for proper voltage. If voltage is less than 11 volts, injection pulse width will increase. This step should be done during the conditions that the DTC sets (cold engine, hot engine).
2. This step checks to see if there is a signal to the PCM.
3. This step will determine if the PCM is receiving the correct signal or if there is a faulty injection pump. For the Fuel Inject Control (CKT 984) duty cycle there is a corresponding duty cycle operating range for the fuel inject signal (CKT 985). If the fuel inject signal (CKT 985 is not in the corresponding operating range there is a problem with the injection pump. If the Fuel Inject Signal (CKT 985) is in the operating range the PCM is not processing the signal.

DIAGNOSTIC AIDS
The injection pulse width will fluctuate when throttle is depressed.
A weak (mechanical failure) fuel solenoid will result in DTC 36.