Help 6.9 problem
Methanoholic
Joined: Mar 2009
Posts: 6,442
Likes: 8
From: Maine (NorCal Native)
***** The following assumes you have already checked cables, connections, cab, chassis and engine grounds. *****
***** That the water temp is below 112F degrees. (ie: cold motor) *****
***** When testing energize briefly, long enough to get the answer, no need to overheat things and no more than 10 seconds *****
Unplug the forward most connector on the Injection pump, this prevents overheating the FSS.
Test light test of the glow plugs:
Test that you get power to the glow plugs:
*** Pre '87 Controller, Relay test. ***
The relay is attached to the right (passenger) inner fender and has 4 terminals.
Reconnect the FSS.
-Enjoy
fh : )_~
***** That the water temp is below 112F degrees. (ie: cold motor) *****
***** When testing energize briefly, long enough to get the answer, no need to overheat things and no more than 10 seconds *****
Unplug the forward most connector on the Injection pump, this prevents overheating the FSS.
Test light test of the glow plugs:
- Unplug the Glow Plugs.
- Attach one end of a test light to 12v+ battery.
- Touch the other end to the terminal on the end of the Glow Plug (where you unplugged the harness)
Does it light up?- Yes, Chances are it's good.
- No, Replace with Motorcraft/Beru ZD1A for 83-86, ZD9 for 87-94.5.
To do a positive test use a volt/ohm meter and test the ohms between the terminal and base. Should be .5 to 1 ohm resistance.
Test that you get power to the glow plugs:
- Unplug a glow plug.
- Attach one end of a test light to the glow plug wire.
- The other end to ground.
- Momentarily turn the key on while watching the test light.
Does it light up?- Yes, test Glow Plugs.
- No, test Controller, Relay.
*** Pre '87 Controller, Relay test. ***
The relay is attached to the right (passenger) inner fender and has 4 terminals.
- 1 large terminal (Input Terminal) goes to full time 12v+. (battery)
- The other large terminal (Output Terminal) goes to the glow plugs.
- 1 small terminal (Power Terminal) is controlled 12v+ from the controller. (Purple wire)
- The other small terminal (Ground Terminal) goes to ground. (white with black tracer (I think))
Ensure there is 12v+ to the Input Terminal of the relay.
Ensure Ground is good, both the base and Ground Terminal.
Relay test:- Attach one end of a test light to ground.
- The other end to the Output Terminal of the relay.
- Remove the small purple wire from the glow plug relay.
- Momentarily apply 12v+ to the Power Terminal on the relay. (where purple wire was)
Does it light up?- Yes, relay MAY BE good.
- Test voltage at the battery and the Output Terminal on the relay while relay is energized. BE QUICK. (10 seconds or less)
- Voltages should be close to the same. If not replace relay.
- No, Relay is not working.
- Yes, relay MAY BE good.
Controller test:- Attach one end of a test light to the relay Power Terminal (purple wire, do not remove from relay)
- The other end to ground.
- Turn the key on while watching the test light.
Leave the key on until the test light goes off (or cycles) or 10 seconds which ever occurs first.
Does it light up?- Yes, The controller MAY BE good.
- Does it go off by itself? (It may cycle, thats good)
- Yes, Controller is good.
- No, The controller has FAILED ON ... Replace!
- Does it go off by itself? (It may cycle, thats good)
- No, The controller is bad replace.
- Yes, The controller MAY BE good.
Reconnect the FSS.
-Enjoy
fh : )_~
