i get a constant 12 volts to one of the large posts on the relay with key on/off. key on, i get 12 volts to both posts till the GP time out.
Key off.....you should have voltage to the large stud on the battery side of the relay and not the other. No voltage to either small terminals.
Key on/Glow Plugs on........you should have voltage on both large relay posts as current is passing through the relay to the GP's. You should also see voltage on both small terminals s as low amperage current is being sent through them to pull in the contacts allowing high amperage current to pass through the relay to the glow plugs.
When the GP's cycle off(key on) you should only see voltage on the one large terminal on the battery side.
the boot that covers one of the large post wires is melted as well as part of the wire where it connects to the terminal.
Prehaps the old relay had partially burnt contacts creating high resistance. That might have burnt the wire and the terminal cover you are discribing and thus the smell.
Does the burnt wire get hot now................???
Tbar
on edit:
......is melted as well as part of the wire where it connects to the terminal.
If you have a partially melted wire it is probably creating high resistance/heat and is continuing to melt the wire insulation. You better check this and R&R asap.
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