Controller Function Test

1987 Ford Cutaway 6.9 1SECTION Controller Function Test

Turn ignition off. Check controller function by connecting a 12-volt test light to test terminal on controller. Position test light so it can be viewed from driver's position. Turn ignition on. Note system operation and compare test light times to TEST LIGHT TIMES  table. If test light times are within specification, system function is correct. If test light times are out of specification, disconnect power at both batteries and replace controller unit. Repeat this step.

TEST LIGHT TIMES

Controller (1) Temp. (°F) (2) "Wait To Start" "ON" Time: Seconds (3) Test Lamp Total Time: Seconds
-20 7-15 35-70
0 7-12 25-60
35 5-12 15-35
70 3-5 7-15
105 1-3 3-5
140 1 or Less 1-3
(1) Temperature of controller unit, NOT ambient temperature.
(2) "Wait To Start" light and/or Test light may not glow if engine is at or near normal operating temperature.
(3) Total Test light "ON" time includes time from beginning of initial "ON" cycle to end of last "ON-OFF" cycle.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.