
Onboard Diagnostics
DIAGNOSTIC TROUBLE CODES (DTCs)
OBD2 17
Manufacturer-Specific DTCs
are codes that are controlled by
the vehicle manufacturers. The Federal Government does not
require vehicle manufacturers to go beyond the standardized
generic DTCs in order to comply with the new OBD2
emissions standards. However, manufacturers are free to
expand beyond the standardized codes to make their systems
easier to diagnose.
The 3rd character is a
numeric digit
. It identifies the specific
system or sub-system where the problem is located.
The 4th and 5th characters are
numeric digits
. They identify the
section of the system that is malfunctioning.
P 0 2 0 1
B
C
P
U
-
-
-
-
Body
Chassis
Powertrain
Network
-
-
-
-
Generic
Manufacturer Specific
Generic
Includes both Generic and Manufacturer
Specific Codes
0
1
2
3
Identifies what section of the system
is malfunctioning
Identifies the system where the
problem is located:
1
2
3
4
5
6
7
8
-
-
-
-
-
-
-
-
Fuel and Air Metering
Fuel and Air Metering (injector circuit
malfunction only)
Ignition System or Misfire
Auxiliary Emission Control System
Vehicle Speed Control and Idle Control
System
Computer Output Circuits
Transmission
Transmission
OBD2 DTC EXAMPLE
P0201 - Injector Circuit Malfunction, Cylinder 1
Summary of Contents for 3130b
Page 1: ......
Page 84: ...Notes 82 OBD2...
Page 85: ...Notes OBD2 83...
Page 86: ...Notes 84 OBD2...