Caterpillar: Accessing Diagnostic Trouble Codes

3100 HEUI, 3116, 3126, 3126B, C7, C9, C10, C11, C12, C13, C15, C16, 3176B & 3406E Engines
Caterpillar Driver information Display (Cat ID) System

Diagnostic data can be displayed on the Cat ID by following the screen map and activating the arrow keys. The PID-FMI codes will be displayed on the screen with a brief description. Codes that indicate a potential engine damaging condition will be automatically displayed on the Cat ID screen. The automatically displayed codes include codes 100-00 high coolant temperature warning, 100-01 low oil pressure warning, 100-11 very low oil pressure, 105-00 high intake air temperature, 105-11 very high air intake temperature, 110-11 very high coolant temperature, 111-01 low coolant level warning and 111-11 very low coolant level.

Using Scan Tool
  1. Turn ignition switch to Off position.
  2. Connect suitably programmed scan tool to Data Link Connector (DLC).
  3. Turn ignition switch to On position.
  4. Follow scan tool manufacturer's instructions to access diagnostic trouble codes.
Flash Codes
  1. Turn ignition switch to On position.
  2. Turn cruise control switch to Off position.
  3. Move Set/Resume switch to either position and hold until yellow Diagnostic lamp begins to flash.
  4. Release Set/Resume switch.
  5. Count first sequence of flashes to determine first Diagnostic Trouble Code (DTC) digit.
  6. After two second pause, count second sequence of flashes to determine second DTC digit.
  7. Additional codes will follow after pause.
3406B PEEC & 3176 Engines
Using Cruise Control Switches
  1. Turn ignition On.
  2. Turn cruise control ON/OFF switch to OFF, move SET/RESUME switch to the RESUME position. Once the codes start to flash the switch can be released.
  3. The diagnostic lamp will come On for five seconds, then Off for five seconds, then repeat the sequence a second time. At the end of the second time the lamp will begin to flash the first number of a two digit code, count the flashes. After two seconds the second digit will begin to flash. After a few seconds if other ACTIVE code are stored they will be displayed in the same manner.
Using Scan Tool
  1. Ensure ignition is Off, then install a suitable electronic service tool.
  2. Turn ignition On. Refer to operating manual and special instructions for service tool used to read diagnostic codes