C 10 1/2 Ton Pickup 2WD V8-379 6.2L DSL VIN C FI (1982)
Pin 3:
(Blue Wire) should have battery voltage with the vehicle
ignition key on.
Pin 4:
(Orange Wire) should have continuity (0 ohms resistance)
to the double red wire terminal on the glow plug relay.
Pin 5:
(Black wire) should have continuity (0 ohms resistance)
to Pin 6 (Black Wire) and to ground.
Pin 6:
(Black Wire) same as Pin 5.
Complaints of a "no start - due to no glow plugs heating" have been received where the no-start problem was a result of a failed delcotron
positive diode.
When the diode fails in the delcotron, battery voltage can be supplied to the glow plug controller with the key off and the engine stopped. This battery
voltage is normally supplied to Pin #1 in the glow plug controller from the delcotron after the engine starts. This voltage, in effect, tells the controller
that the engine has started and shuts off the glow plug heating cycle.
When a "no glow plug heating" problem is received, a quick check should be made to see if a diode failure is the cause.
Follow this procedure:
1.
With the key off and the engine stopped, check for voltage in the brown wire that goes from the delcotron to the glow plug controller.
2.
If a voltage is present, disconnect the wire from the delcotron. Again, check the voltage in the brown wire. There should be none. (If the key is
"on", a low voltage, approximately 3 volts, will be present in a properly operating system.)
3.
Wait for a minimum of fifteen (15) minutes, or sufficient time for the controller to cool off.
4.
Turn the key on. If the glow plugs heat, the problem was with the delcotron.
NOTICE:
The only time battery voltage should be present in the brown wire is when the engine is running. With the key on, and the engine not
running, a low voltage (approximately 3 volts) will be present in the brown wire. This is normal.
