Caterpillar 3126B — Engine Diagnostics (Flash Codes)

Testing & diagnosis

For the Caterpillar 3126B, from the Caterpillar owner's manual.

Applies to: Caterpillar 3126B

Procedure

1. Turn cruise control switch to OFF position.
2. Move SET/RESUME switch to either position and hold.
3. Record two-digit flash codes: short pause between digits, long pause between codes.
4. Refer to Engine Diagnostics table in the O & M manual and consult your local Caterpillar dealer.
5. Flash code 55 is “No Detected Faults.”

Full service-parts list: Caterpillar 3126B →

Source: Caterpillar owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.

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