Reprogramming File Availability for DTC P0137 and Improvement of Engine RPM (Idle) Drop Condition – 2015 Subaru Legacy & Outback

NUMBER: 11-160-15
DATE: 09/14/15

APPLICABILITY:	2015MY Legacy & Outback, 2.5L and 3.6L Models
SUBJECT:	Reprogramming File Availability for DTC P0137 and Improvement of Engine RPM (Idle) Drop Condition

 

INTRODUCTION

This bulletin announces availability of reprogramming files to optimize the ECM for DTC P0137.  These files will also address customer concerns of engine idle RPM drop after a hot engine restart on 2.5L models and when shifting from reverse to drive after a cold start on 3.6L models.

 

PACK FILE APPLICABILITY

MODEL YEAR/ MODEL	EMISSION SPEC.	PAK FILE NAME	NEW ECM PART NUMBER	OLD ECM PART NUMBER	TRANSMISSION	NEW CID NUMBER
2015MY Legacy & Outback 2.5L	CAL**	22765AF36D.pak	22765AF36D	22765AF36A	EB4G400C	EB4GA00C
				22765AF36B	EB4G401C
				22765AF36C	EB4G600C
	CAL**	22765AK16B.pak	22765AK16B	22765AK16A	N/A	EB4GA00c
	FED	22765AF35D.pak	22765AF35D	22765AF35A 22765AF35B 22765AF35C		EB4GA00B
2015MY 3.6L	FED	22765AF45C.pak	22765AF45C	22765AF45A 22765AF45B		DB4GA00D

 

**  IMPORTANT NOTE:  On these CAL Emission Specification vehicles, verify the current (OLD) CID number first then use the CID Search function in FlashWrite to determine which new reprogramming file is applicable to the vehicle being repaired.

 

SERVICE PROCEDURE / INFORMATION

IMPORTANT: Before beginning this reprogramming procedure, if P0137 is stored, the FreezeFrame Data (FFD) MUST be reviewed first to eliminate a faulty O2 sensor as the root cause of the

DTC.  In the case of an RPM drop, although this condition will in most cases not cause the Check Engine light to come on, the ECM will likely store a DTC P1603 and the corresponding FFD.  In either of these cases, the stored FFD MUST be reviewed and compared to the information provided below to rule out other possible causes of the stored DTC before installing any of these ECM updates. If your FFD looks very different from the examples outlined, then another cause is suspected.  In that case, follow the appropriate troubleshooting in the applicable Service Manual to determine the cause.

 

P0137 INFORMATION:

 

The O2 sensor temperature is controlled by the ECM and maintained using a heater to keep it within a certain range.  The heater works with predetermined voltages depending on driving conditions.  When exhaust gases heat the sensor, less heater voltage is required.  The purpose of heater voltage control is to avoid overheating the sensor at the same time it is being heated by exhaust gas.  The ECM judges the O2 sensor has been activated and therefore reduces the heater voltage.  In Scenario #1 the sensor cools down due to the long fuel cut condition caused by the long downhill (coasting condition, 0% Calculated load value) shown in the first SSM screenshot above.  Scenario #1 also shows the DTC setting at about 30 minutes since engine start although the second FFD example shows the DTC setting at about 1 minute after engine start.

Scenario #2 shows this DTC can set at almost any time during the first 1 to 40 minutes after engine start under varying load, temperature and vehicle speed conditions.  A “cold” O2 sensor will not work properly and eventually cause the CEL to illuminate.  In this update, the ECM logic has been optimized accordingly to improve control of O2 sensor heater voltage.

IDLE DROP (DTC P1603) INFORMATION:

FOR 2.5L MODELS:

DTC P1603 will be stored (with FFD) whenever the engine speed drops below 300 RPM for 48 milliseconds (ms) BUT, it will not cause the CEL to illuminate.  The FFD stored should be used to help determine a cause for the condition.  In Scenario #3 on page 3, the engine is fully warmed up and was restarted after a (approximate) 10-minute hot-soak.  The FFD shows P1603 set within 5 seconds after restarting the hot engine with “0” vehicle speed and shifter in Neutral.  The idle was OK at first but the rpm drop occurred shortly thereafter. The cause of the rpm drop is fuel vaporization in the fuel rails due to high under-hood temperatures.  In this update, the ECM logic has been optimized providing an improved fuel mixture to overcome the effects of vaporization.

 

There is also a PID called “IG OFF Elapsed Time” which can be used to determine the length of the hot soak prior to setting the DTC.

FOR 3.6L MODELS: 

In some cases, an rpm drop can occur when shifting from Reverse to Drive after a cold start.  The FFD in Scenario #4 shows P1603 set within about 15 seconds after starting the cold engine with a very low vehicle speed and the shifter in Drive.  Under these conditions, a slight increase of throttle opening is needed to compensate for the additional engine torque requirement needed after the shift into Drive.  The ECM logic has been optimized to make this compensation occur sooner after the shift into Drive occurs thereby eliminating the rpm drop.

 

NOTES:

SOA now highly recommends connecting the Midtronics GR8 Diagnostic Battery Charger to the vehicle and utilizing the Power Supply Mode feature anytime a vehicle control module is being reprogrammed. Once the GR8 is connected to the vehicle, as long as the battery is fully charged, it takes less than 3 minutes to boot-up the charger, select the Power Supply Mode, and have the battery voltage stabilized and ready for reprogramming.

VERY IMPORTANT: This information is applicable to the Midtronics GR8 Diagnostic Battery Charger ONLY. It does not apply to any other brand / type of “generic” battery charger

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whatsoever.  ONLY the GR8 and its Power Supply Mode feature has been tested and approved by Subaru of America, Inc. (SOA).

• If the GR8 indicates the vehicle’s battery must be charged, charge the battery using the GR8 before proceeding to reprogram the vehicle while using the Power Supply Mode.
• Control module failures as a result of battery discharge during reprogramming are not a matter for warranty. Should any DTCs reset after the reprogramming update is performed, diagnose per the procedure outlined in the applicable Service Manual.

 

WARRANTY / CLAIM INFORMATION

For vehicles within the Basic New Car Limited and / or Emissions Warranty period, this repair may be submitted using the following claim information:

LABOR DESCRIPTION	LABOR OPERATION #	FAIL CODE	LABOR TIME
MFI OBDII ECM Reprogramming	A455-288	UPG-48	0.4

 

IMPORTANT:  The NEW Calibration Identification number (CID) for any newly-installed programming (as confirmed from the actual control module AFTER installation) MUST be noted on the repair order as this information is required for claim submission.

NOTE:  The pack file listings provided in this bulletin are the latest available at the time of publishing.  Updates are often released thereafter without revision to the original bulletin.  For this reason, it is critical to always have the latest version of Select Monitor III software installed on your system.  You can confirm if a later version is available by entering the CID listed in this bulletin into FlashWrite.  If a newer CID is shown as available in FlashWrite, reprogram using that file.

REMINDER:  SOA strongly discourages the printing and/or local storage of service information as previously released information and electronic publications may be updated at any time.

Always refer to STIS for the latest service information before performing any repairs.

 

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J2534 Reprogramming

Subaru reprogramming files using a generic (non-OEM) SAEJ2534 pass-thru vehicle programming device

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are available by contacting Service Technical Information Company toll free at 1-866-428-2278. The cost for the CD-ROM with all reprogramming files is $75.00 plus S/H and applicable state tax. Files will be updated four (4) times per year, in CD-ROM format, with all available reprogramming service information at the same above offered cost. Authorized Subaru Dealers are provided the same reprogramming information.

Before purchasing, the reprogramming details can be found in the following Reprogramming J-2534 Files chart. Click the link to view the PDF chart.

Subaru J2534 Reprogramming software meets the latest available J2534-1 specification. Our Reprogramming J2534 Files chart does not specify the Calibration Identification Number (CID); however, this information is included in our offered CD-Rom.

Note: The ECM or TCM being reprogrammed may already contain some or all of the reprogramming files listed in the Reprogramming J2534 Files chart shown by release date. It is possible to damage the vehicles ECM/TCM during the reprogramming event. Once the reprogramming process has started, it is recommended not to interrupt the process until the event is completed. If you experience any problems, please contact your scan tool maker for further instructions.

Are all pre-2004MY Subaru vehicles compatible with J2534?

No. Subaru has no reprogramming capability for model years 1996-1998. Starting with our 1999 model year, please see our Reprogramming Pre-J2534 Files chart for affected model reprogramming information.

Both pre-J2534 reprogramming and J2534 pass thru reprogramming files are included in the offered HDS kit software for aftermarket service provider application.

techinfo.subaru.com

 

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