LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Pontiac >> 2000 >> Firebird Formula, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Self-Diagnostics - 5.7L >> Diagnostic Tests >> DTC P1258: Engine Coolant OVERTEMPERATURE - Protection Mode Active >> Diagnostic Procedures
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic Procedures

  1. Perform On-Board Diagnostic (OBD) system check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK . After performing OBD system check, go to next step.
  2. Using scan tool, select CAPTURE INFO, REVIEW INFO function. If other ECT related DTC(s) are present, diagnose affected DTC(s). If no other DTC(s) are present, repair cooling system or mechanical problem as necessary.
scientia non olet · About LEMON Manuals