Neon L4-2.0L DOHC (1996)
Powertrain Control Module: Description and Operation
PCM Related Trouble Code Messages
Internal Controller Failure
WHEN MONITORED
With the ignition ON
SET CONDITION
There is an EPROM sum check failure at power down.
THEORY OF OPERATION
This code indicates the EPROM memory may be corrupt.
PROBABLE CAUSES
-
Failed PCM
PCM Failure EEPROM Write Denied
Unsuccessful attempt to write to an EEPROM location by the PCM.
PCM Failure SPI Communications
WHEN MONITORED
With the ignition ON.
SET CONDITION
Serial communications inside the controller fail eight times.
THEORY OF OPERATION
Communication between the microprocessors inside the PCM is needed to operate the total system.
-
A failure to communicate may cause improper actuation of the solenoids and relays.
PROBABLE CAUSES
-
PCM failure
PCM Failure SRI Mile Not Stored
Unsuccessful attempt to update EMR mileage in the PCM EEPROM.
5 Volt Supply Output Too Low
Name of Code:
5-Volt Supply Output Too Low
When Monitored:
With the ignition on.
Set Condition:
The 5-volt supply to the sensors is below 3.5 volts for 4 seconds.
Theory of Operation:
The powertrain control module maintains a 5-volt supply to the MAP sensor, TP sensor, and A/C pressure sensor. It is critical that the 5-volt
supply stays between 4.8 volts and 5.1 volts as this input has a direct effect on the sensors' output voltages.
Possible Causes:
-
Shorted 5-volt supply
-
Shorted sensor
