Operation CHARM: Car repair manuals for everyone.

Exciter Circuit, Resistance Checking

If customer complaint ``battery isn't being charged'' is received even though warning light comes on when ignition is switched On and goes out when ignition is turned Off, check exciter circuit resistance as follows:
1. Disconnect battery ground cable.
2. Disconnect blue wire (D +/61) from back of alternator.
3. Switch multimeter US 1119 or equivalent to 200 ohm range.
4. Connect multimeter between disconnected blue wire and battery positive terminal.
5. Turn ignition switch to On position.
6. Reading should be 140-160 ohs.
7. If reading is infinite, reverse probes and recheck.
8. If reading is still infinite, printed circuit must be replaced.