New info for Repair Database?

[dejongmc]

I was surfing on the internet looking for info regarding the Drive Cycle for a '97 Volvo 850 NA and found the following info, but very helpfull:
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Emissions - Establishing OBDII Readiness Codes
Notes

NO: 25-19

DATE: 6-30-2004
MODEL:
960 - S/V 90/850/S70/V70/C70

M. YEAR:
1996-1998

SUBJECT:
Establishing Readiness for OBD II


DESCRIPTION:

As part of vehicle inspection programs various states have introduced a check of the vehicle Onboard Diagnostic System (OBD II). This inspection will check the operation of the malfunction indicator lamp (MIL), and scan for Diagnostic Trouble Codes (DTCs) and OBD II Readiness Codes within the electronic emission control system.

These programs have been introduced at the request of various State or Federal government agencies to assist states in meeting Clean Air Standards as required by Federal law and are applicable to all model year 1996 and later light-duty vehicles.

The OBD II system is a comprehensive system that is part of the vehicle Engine Management System that helps diagnose potential faults within the emission control system. The monitors within the OBD II system can provide very useful information about the status of the on board emission control system. These monitors indicate whether the emission system is, or is not, operating correctly and provide a fault code to help identify the malfunctioning system or component. This eliminates the traditional tail pipe exhaust gas test and expediting the inspection process.

Readiness is the method used to confirm that all of the engine management system emissions related on-board diagnostics have run successfully and no faults were detected. Readiness is only an indication that the diagnostic has run successfully The MY 1996 to 1998 Volvo are 'TRIP' based for establishing readiness. This requires two 'TRIPS' to be completed in order to reset readiness codes from 'NOT READY' to 'READY'. A 'TRIP' is identified in the Engine Management System Service Manuals TP 2308202 M 4.4, section KKKK, TP 2301202 M 4.3, section EBU, and TP2321201 M 4.4 (900) section VVV.

Following the procedures in these manuals may not allow all of the diagnostic monitors to run. The instructions listed in this bulletin will exercise all of the diagnostic monitors on these models. Upon completion of two trips and no diagnostic trouble codes are present; the readiness codes should be set to 'READY'.

A monitor remaining 'NOT READY' only indicates that the driving conditions for the diagnostic to run have not yet been met. There are several reasons the monitor status may be 'NOT READY', such as;
1. The battery has been disconnected for service and the ECM memory is erased.

2. A DTC has been erased from the ECM, resulting in readiness is re-set to 'NOT READY'

3. The driver may not normally drive far enough or in a pattern that readiness is completed during the drive.



General Instructions

1. No Diagnostic Trouble Codes (DTC) should be present in the ECM or TCM.

2. Fly wheel adaptation must be completed before diagnostics can run (Refer to Driving to change the flywheel status to "Ready").

3. Connect Volvo Systems Tester (VST). Enter the DIAGNOSTIC CHECK menu to verify if a trip has been completed as shown. Please Note: If using a scan tool other than the VST, different terms for reporting the same status may be displayed. 'READY' may be displayed as 'COMPLETE' and, 'NOT READY' may be displayed as INCOMPLETE'.

4. In order to insure EVAP leakage detection completion, the fuel level in the car should be above 1/4 and below 3/4 tank.

5. Air conditioning (A/C) must be off during idle periods. A/C compressor activation during the EVAP diagnostic may interrupt the EVAP test.

6. Select a suitable route where it is possible to achieve necessary speed and load conditions and occasionally stop at the side of the road safely. This needs to be done while obeying all traffic regulations and posted speed limits.

7. Important: Keep as steady a throttle pedal as possible when driving.

8. Engine temperature at start must be between + 29

[hanseich]

Hi dejongmc,

this information is very interesting. I failed an emissions test in Ontario today. I tried to reset the ECU, but failed to do the driving trip twice (since the trip needs to be done from a cold engine, I couldn't do it twice last night). How can I tell whether the driving reset the ECU? My HC and CO% levels were high. Can it be that they both drop down by 50% if the ECU is READY?

I've got all the details about my values posted here:
https://www.matthewsvolvosite.com/forums ... 74#p258752