Cavalier L4-2.2L VIN 4 (1998)
PROM - Programmable Read Only Memory: Customer Interest
PCM - DTC U1016 Stored With No Symptoms
File In Section: 6E - Engine Fuel & Emission
Bulletin No.: 87-65-19
Date: May, 1998
Subject:
DTC U1016, Stored Code with No Active Symptoms
(Reprogram PCM)
Models:
1998 Chevrolet Cavalier
1998 Pontiac Sunfire with 2.2L, 2.4L Engine (VINs 4, T - RPOs LN2, LD9) with Automatic Transmission Only
Condition
During diagnosis for various unrelated conditions, a DTC U1016 may be noted as stored in the PCM with no active symptoms.
If there were an actual failure, this code would be accompanied by a similar code in the IP cluster or in each of the devices on the UART line.
Cause
A calibration error may induce the PCM to store DTC U1016 as an inactive stored history code during vehicle key-down.
Correction
If during diagnostics for other conditions, a DTC U1016 is noted without any symptoms that are part of the parameter for setting the U1016 code,
reprogram the PCM with the appropriate calibration from the list. These calibrations are available on 1998 CD-ROM # 9 and later versions.
Service Procedure
1.
Install a scan tool and verify that the previously noted DTC is set.
2.
Note the calibration ID currently in the PCM.
3.
Reprogram the PCM with the Calibration Number listed in the table.
4.
Operate the vehicle and check for any additional DTC's.
5.
If the vehicle exhibits a U1016 code after being reprogrammed, review the appropriate Service Manual diagnostic procedures.
Calibration Numbers
