PCM Diagnostics Results

[MoshimoGTP]

There are the results of the PCM Diagnostic with a OTC Diagnostic Tool:

P0706 (D) - TRANS RANGE SW PERF
P0441 (B) - EVAP SYS NO FLOW
P0300 - MISFIRE DETECTED
P0122 (A) - TP SENS CKT VOLT
P0102 (A) - MAF SENS CKT LOW FREQ
P1374 (B) - 3X REF CKT (WHAT ARE THIS????????????????)

The PCM Was reseted by OTC and the SES Light come off. But 2 days later the SES Light come on again. I will diagnose again the PCM.

Comments?

[Ripn12s]

300 - Misfire - get some new plugs and wires and use plenty of dialectric grease
--------------------------------------------------------------------
706-

Conditions for setting this code:

The transaxle Range Switch indicate a gear position other than Park or Neutral during startup

The above conditions are present for 2 consecutive setups

Easiest thing the book says to check is, make sure the PCM wireharness is ok. Also, if you have access to a scan tool, move the gear selector and see if the PCM corresponds to the selected gear.

Sounds like either a new PCM or a Trans Range Switch might be needed

----------------------------------------------------------------------
441 - cant find in my book Might check to make sure your gas cap is working properly
------------------------------------------------------------------
122 - Throttle Position Sensor

The TP signal is one of the most important inputs used by the PCM for fuel control and most of the PCM - controlled outputs.

Inspect wiring harness

Once again a shop could probably find the problem easier, but the book breaks it down to bad sensor or bad PCM if no bad connections are found on the wiring harness.
-------------------------------------------------------------------

102 - MAF sensor measures the amount of air which passes through it into the engine during a given time. The PCM uses the mass air flow info to monitor engine operating conditions for fuel delivery calculations. A code will set if the signal frequency from the MAF sensor is lower than the possible range of a normally operating MAF sensor. The freq. will vary within a range of around 2000 hertz at idle to about 10000 hertz at max engine load.

Once again the book talks about checking the connections to the sensors and PCM and replacing the sensor or PCM
---------------------------------------------------------------------
1374- The 3x reference signal is produced by the ignition control. The ICM calculates the 3x reference signal by dividing the crankshaft position sensor 18x by 3 when the engine is running and the CKP sync pulses are also being received. The PCM uses the 3x ref. sig. to calculate engine rpm and crankshaft position at engine speeds above 1200 rpm. The pCM also uses the pulses on this circuit to initiate injector pulses. The PCM constantly monitors the number of pulses on the 3x ref circuit and compares the number of 3x ref pulses to the number of 18 x ref. pulses and CAM signal pulses being received.

If the PCM receives an incorrect number of pulses on the 3x ref. circuit, DTC 1374 will set and the PCM will use the 18x ref sig. circuit for fuel and ignition control.

Diagnostic Aids:

Poor Connection - inspect harness and connectors for improper mating

Damaged harness

Malfunctioning Ignition Coil

Replace Ignition Control Module
Replace PCM
----------------------------------------------------------------------


This is just some info i got off my GM manual. Hope it helps alittle

Tim

[kilroypr]

441 could be related to the return flow to the gas tank from the Throtle Body/intake system. COuld be a broken return line or clogged purge canister

[GhostLake]

The 441 could also be the evap purge solenoid.

[MoshimoGTP]

these are bad news... or not???... =(