Engine or A/C System - Poor Performance
NUMBER: 18-16-00GROUP: Vehicle Performance
DATE: Sept.15, 2000
SUBJECT:
Poor A/C Or Engine Performance
OVERVIEW:
This bulletin involves selectively erasing and reprogramming the Powertrain Control Module (PCM) with new software.
MODELS:
2001 (PL) Neon
NOTE:
THIS INFORMATION APPLIES TO VEHICLES BUILT PRIOR TO AUGUST 28, 2000 (MDHO828XX).
SYMPTOM/CONDITION:
Some vehicles may exhibit one or more symptom/conditions as follows:
Poor A/C Performance In High Ambient Temperatures
During high under hood temperatures with the engine coolant temperature less than 100°C (212°F), the A/C compressor may repeatedly disengage due to high head pressure. Disengagement of the A/C compressor may continue until speeds of 40 Kph (25 Mph) or more are reached.
Poor Engine Performance In City Traffic During High Ambient Temperatures During high temperatures (greater than 35°C [95°F]) in stop and go traffic (at least 30 minutes). Some vehicle may exhibit poor acceleration (0 to 40 Kph [0 to 25 Mph] in 20 seconds) or experience difficulty exceeding 96 Kph (60 Mph). Cooling the engine corrects the condition.
Engine Speed Undershoot Due To High DI Fuel
In ambient conditions between 15°C and 26°C (60°F and 80°F) with the HVAC system set to A/C or defrost on an initial cold start. Some vehicles may exhibit an idle speed drop to approximately 400 rpm on the first A/C compressor engagement. Later A/C engagements are without occurrence. See TSB 14-08-97 dated Nov. 21, 1997 for a detailed explanation of High DI fuel.
DIAGNOSIS:
Using the Mopar Diagnostic System (MDS2) and or the Diagnostic Scan Tool (DRB III 7) with the appropriate Diagnostic Procedures, verify all engine/transmission systems are functioning as designed. If other Diagnostic Trouble Codes (DTC's) are present, record them on the repair order and repair as necessary before proceeding further with this bulletin. If the condition(s) can be duplicated or is described by the customer, perform the Repair Procedure.
NOTE:
WHENEVER A POWERTRAIN CONTROL MODULE (PCM) IS REPLACED, THE SOFTWARE OF THE REPLACEMENT CONTROLLER MUST BE VERIFIED FOR THE LATEST REVISION LEVEL. USE THE FLASH PROCEDURE TO UPDATE REPLACED CONTROLLERS AS NECESSARY.
PARTS REQUIRED:
EQUIPMENT REQUIRED:
NOTE:
THE MDS2 AND DRB III(R) ARE REQUIRED TO PERFORM PART OF THIS REPAIR. THE MDS2 SYSTEM MUST BE OPERATING AT CIS CD2067 OR HIGHER.
REPAIR PROCEDURE:
1. Log onto the MDS2 system.
2. Connect the MDS2 (Mopar Diagnostic System) and DRB III(R) (Scan Tool) to the vehicle and switch the ignition key to "ON".
NOTE:
AUTO CONNECTION WILL OCCUR ONCE THE DRB III(R), MDS2 AND VEHICLE ESTABLISH COMMUNICATION. THE "CANNOT READ VIN FROM DRB III(R)" MESSAGE (ON THE MDS2) WILL BE REPLACED BY THE VEHICLE VIN. PRESS THE "OK" BUTTON ON THE MDS2 TO REQUEST A MDS2 SESSION FOR THE VEHICLE VIN INDICATED. PRESS THE "OK" BUTTON WHEN ASKED TO BEGIN SESSION.
3. Push the FLASH tab on the MDS2.
4. Select READ PART NUMBERS FROM VEHICLE and click SHOW UPDATES on the MDS2.
NOTE:
A MESSAGE MAY APPEAR (AFTER STEP 3 OR 4) THAT INDICATES NO UPDATES ARE AVAILABLE. IF THIS OCCURS, MAKE SURE YOUR DIAGNOSTIC EQUIPMENT IS OPERATING AT THE LATEST SOFTWARE LEVEL AS LISTED EARLIER IN THIS BULLETIN. IF THE LATEST SOFTWARE IS INSTALLED, AND NO UPDATES ARE AVAILABLE, ANOTHER VEHICLE CONDITION EXISTS THAT WILL REQUIRE FURTHER INVESTIGATION.
5. Select the new software part number with the light pen and click UPDATE CONTROLLER SOFTWARE.
6. The MDS2 and DRB III(R) will prompt for any operator action needed during the remainder of the reprogramming process.
NOTE:
THE FOLLOWING STEPS ARE REQUIRED BY LAW.
7. Type the necessary information on the "Authorized Software Update Label" p/n 04669020 (Figure 1). Attach the label to the PCM and cover the label with the clear plastic overlay.
8. Type the necessary information on the "Authorized Modification Label" p/n 04275086 and attach the label near the VECI label (Figure 2).
POLICY: Reimbursable within the provisions of the warranty.
TIME ALLOWANCE:
FAILURE CODE: FM - Flash Module