Diagnostic Aids
After engine is started, temperature should rise steadily to approximately 194°F (90°C), and then stabilize when thermostat opens. When a Code 14A is set, ECM will turn on engine cooling fan. Code 14A will set if circuit No. D12 is shorted to ground. For intermittent inspection, see INTERMITTENTS in TROUBLE SHOOTING - NO CODES - FUEL INJECTION article.