MICROSCAN User Manual - Snap-on

On-Board Diagnostics (OBD) Diagnostic Service Definitions
4.6.6 Service $06: Specific Monitored Systems Test Results
The purpose of this service is to allow access to the test results for on-board diagnostic monitoring
tests of specific components or systems that are continuously monitored (CAN only) and
non-continously monitored.
The misfire monitor is an example of a continuously monitored system, and the catalyst system
would be an example of a non-continously monitored system.
CAN Protocol
For CAN the Test ID Table from Service $05 is used. The request message for test values includes
an OBDMID (On-Board Diagnostic Monitor IDentification) that indicates the information
requested. Unit information is given with the values. Test values (results) are always reported with
the minimum and maximum test limits.
IMPORTANT:
The Test ID Table below is for CAN Protocol only:
Table 4-6 Test ID Table for CAN Protocol
Test ID No. Description
$01 Rich to Lean sensor threshold voltage, (Constant)
$02 Lean to Rich sensor threshold voltage, (Constant)
$03
Low sensor voltage for switch time calculation,
(Constant)
$04
If an OBDMID has not been completed at least once since Service $04 or battery disconnect, then
the following properties of the parameter are set to zero by the ECM:
• Test Value (Results)
• Minimum Test Limit
• Maximum Test Limit
High sensor voltage for switch time calculation,
(Constant)
$05 Rich to Lean sensor switch time, (Calculated)
$06 Lean to Rich sensor switch time, (Calculated)
$07 Minimum sensor voltage for test cycle, (Calculated)
$08 Maximum sensor voltage for test cycle, (Calculated)
$09 Time between sensor transitions, (Calculated)
$0A Sensor Period, (Calculated)
EWMA (Exponential Weighted Moving Average)
misfire counts for last 10 driving cycles (calculated)
$0B
Calculation: 0.1 * (current counts) + 0.9 * (previous
average)
Initial value for (previous average) = 0
$0C
Misfire counts for last/current driving cycles
(calculated)
24