User Manual

⚫ Stored Codes

Stored codes are the current emission related DTCs from the ECM of the vehicle.

OBD II/EOBD Codes have a priority according to their emission severity, with

higher priority codes overwriting lower priority codes. The priority of the code

determines the illumination of the Malfunction Indicator Light (MIL) and the codes

erase procedure. Manufacturers rank codes differently, so expect to see

differences between vehicles.

⚫ Pending Codes

These are codes whose setting conditions were met during the last drive cycle, but

need to be met on two or more consecutive drive cycles before the DTC actually

sets. The intended use of this service is to assist the service technician after a

vehicle repair and after clearing diagnostic information, by reporting test results

after a single driving cycle.

a) If a test failed during the driving cycle, the DTC associated with that test is

reported. If the pending fault does not occur again within 40 to 80 warm-up

cycles, the fault is automatically cleared from memory.

b) Test results reported by this service do not necessarily indicate a faulty

component or system. If test results indicate another failure after additional

driving, then a DTC is set to indicate a faulty component or system, and the

MIL is illuminated.

⚫ Freeze Frame

In most cases the stored frame is the last DTC that occurred. Certain DTCs, those

that have a greater impact on vehicle emission, have a higher priority. In these

cases, the highest priority DTC is the one for which the freeze frame records are

retained. Freeze frame data includes a “snapshot” of critical parameter values at

the time the DTC is set.

⚫ Erase Codes

This option is used to clear all emission related diagnostic data such as, DTCs,

freeze frame data and manufacturer specific enhanced data from the vehicle’s

ECM, and resets the I/M Readiness Monitor Status for all vehicle monitors to Not

Ready or Not Complete status.

A confirmation screen displays when the clear codes option is selected to prevent

accidental loss of data. Select Yes on the confirmation screen to continue, or No to

exit.

I/M Readiness

This function is used to check the readiness of the monitoring system. It is an excellent

function to use prior to having a vehicle inspected for compliance to a state emissions

program. Selecting I/M Readiness opens a submenu with two choices:

⚫ Since DTCs Cleared – displays the status of monitors since the last time the DTCs

are erased.