LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Cadillac >> 2012 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 1136 (Engine Cooling System) >> Diagnostic Information and Procedures >> DTC P1258 >> Circuit/System Testing
July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!

Circuit/System Testing

WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
  1. Test the thermostat for correct operation. Refer to Thermostat Diagnosis (LP1, LY7)  or Thermostat Diagnosis (LS2) .
  2. Test the engine cooling system for overheating. Refer to Engine Overheating (LP1, LY7) .
  3. Inspect the water pump and coolant flow for correct operation. Refer to Water Pump Replacement (LY7, LLT) .
  4. Inspect the engine mechanical for worn/leaking/cracked cylinder heads and engine block. Refer to Coolant in Combustion Chamber and Coolant in Engine Oil .
scientia non olet · About LEMON Manuals