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Test 12: THERMO Timer

  1. Check that timer is properly installed and firmly seated. Check radiator for correct coolant level. Bleed cooling system.
  2. Disconnect timer and check resistance values between plug terminals "G" and "W", "G" and ground, and "W" and ground. If values are correct, trace timer circuit and repair wiring. If values are incorrect, replace timer. See the THERMO TIMER RESISTANCE SPECIFICATIONS  table.
THERMO TIMER RESISTANCE SPECIFICATIONS

Circuit Tested Resistance
"G" to Ground 40-70 Ohms
"G" to "W" & "W" to Ground
Above 60°F (15°C) Infinite
Below 60°F (15°C) Zero