Diagnostic Trouble Codes (Dtcs) - Innova 3100 Owner's Manual

Do not confuse a "Trip" Drive Cycle with an OBD 2 Drive
Cycle. A Trip Drive Cycle provides the "Enabling Criteria" for
one specific Monitor to run and complete its diagnostic
testing. An OBD 2 Drive Cycle must meet the "Enabling
Criteria" for all Monitors on a particular vehicle to run and
complete their diagnostic testing.
Warm-up Cycle - Vehicle operation after an engine off period
where engine temperature rises at least 40°F (22°C) from its
temperature before starting, and reaches at least 160°F (70°C).
The PCM uses warm-up cycles as a counter to automatically
erase a specific code and related data from its memory. When no
faults related to the original problem are detected within a
specified number of warm-up cycles, the code is erased
automatically.

DIAGNOSTIC TROUBLE CODES (DTCs)

Diagnostic Trouble Codes (DTCs) are
meant to guide you to the proper
service procedure in the vehicle's
service manual. DO NOT replace
parts based only on DTCs without first
consulting the vehicle's service
manual for proper testing procedures for that particular
system, circuit or component.
DTCs are alphanumeric codes that are used to identify a
problem that is present in any of the systems that are
monitored by the on-board computer (PCM). Each trouble
code has an assigned message that identifies the circuit,
component or system area where the problem was found.
OBD 2 diagnostic trouble codes are made up of five
characters:
The 1st character is a letter. It identifies the "main system" where
the fault occurred (Body, Chassis, Powertrain, or Network).
The 2nd character is a numeric digit. It identifies the "type" of
code (Generic or Manufacturer-Specific).
Generic DTCs are codes that are used by all vehicle
manufacturers. The standards for generic DTCs, as well as
their definitions, are set by the Society of Automotive
Engineers (SAE).
Manufacturer-Specific DTCs are codes that are controlled
by the vehicle manufacturer. The Federal Government does
not require manufacturer-specific codes in order to comply
with the new OBD 2 emissions standards. However,
manufacturers are free to expand beyond the required
codes to make their systems easier to diagnose.
OBD 2
Learning More
DIAGNOSTIC TROUBLE CODES (DTCs)
Diagnostic Trouble
Codes (DTCs) are codes
that identify a specific
problem area.
35