SENR9977 23 Systems Operation Section Electronic Control Module (ECM) Flash programming is the method of programming or updating the personality module. Refer to Troubleshooting, RENR2696, “Flash Programming ” for the instructions on the flash programming of the personality module. The ECM is sealed and the ECM needs no routine adjustment or maintenance. Pressure Sensors g01133234 Illustration 26 Electronic control module (ECM) The ECM functions as the governor and the computer for the fuel system. The ECM receives all the signals from the sensors in order to control the timing and the engine speed.
g00884730 Illustration 27 Intake manifold pressure sensor The intake manifold pressure sensor is a three-wire active sensor that is supplied with power from the ECM. The sensor provides the ECM with a measurement of intake manifold pressure in order to control the air/fuel ratio. This will reduce the engine smoke during transient conditions. The intake manifold pressure sensor is also used for engine monitoring. Reprogramming of the ECM requires factory passwords. The reasons for having passwords in an ECM are the following reasons: Prevent unauthorized reprogramming. Prevent unauthorized erasing of logged events. Allow the customer to control certain programmable engine parameters.
The operating range for the intake manifold pressure sensor ................ 55 kPa to 339 kPa (8 psi to 50 psi) Required accuracy ......... ±3% of maximum pressure The factory passwords restrict changes to authorized personnel. Factory passwords are required to clear any event code. Refer to Troubleshooting, RENR2696, “Factory Passwords” for more information on the passwords. The ECM has an excellent record of reliability. Any problems in the system are most likely to be the connectors and the wiring harness. The ECM should be the last item in troubleshooting the engine. The personality module contains the software with all the fuel setting information.
The information determines the engine performance. The personality module is installed behind the access panel on the ECM. g01133306 Illustration 28 Engine oil pressure sensor (1) Sensor common (2) 5 volt supply (3) Pressure signal