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Alright as posted before, I am still having problems with the idiot lights on my 65 coupe. I have replaced all wiring (underdash, engine feed, headlight/VR, and the alternator lead) per Jim Osbourn Diagram, and the car has new battery cables, alternator, voltage regulator (have been tested and are good). My question is that my radio suppressor on the alternator has a bad lead wire on it so I removed it from car. The radio suppressor does not affect the charging system does it? Does it need to plugged into the connector to charge? I know I am grasping at straws here. ::
 

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With FM radios now used in a majority of cars and regulators going to electronic form, ignition radiation suppression capacitors (condensers) are not needed. The only time you need them is if you have an old AM radio and listen to it a lot. With the capacitor removed and listening to AM you may hear ignition noise in the audio you're listening to. If this happens, reinstall the capacitor. Note that NAPA has a lot of these still in their catalog and stock. Any one will do...they're all about the same. I use a GM part in my car. I bought it at NAPA then simply changed the connector on the end of the wire to a Ford bullet connector. Cost $2.50...sure beats $25 NPD wanted for the same item with the Ford connector on the end.
 

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If you are talking about the radio suppression capacitor itself, the answer is no it doesn't have to be attached to the alternator harness. Mine isn't and I have no charging problems. I also don't have any radio interference so I never bothered to replace it.

Frank
 

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One problem you might have overlooked is the ground at the Voltage regulator: a wire that goes to the underside of one of the fastening bolts. The paint under that bolt head has to be removed for it to ground properly.

I've no idea if this will help, but it is often overlooked. What triggered my memory is that the radio capacitor do-hickey is also attached to that grounding point.
 

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Well, it should work, but let's try a different approach. First off, are you just talking about the ALT light, or ALL the idiot lights? I assume just the ALT light. With everything connected as it should be, you should have battery voltage at the following locations:

Key OFF

Alternator BIG terminal
Regulator A terminal

Key ON

Regulator I terminal

Okay so far?

Now, connect a voltmeter to the battery + and -. Remove the plug from the regulator and start the engine. Connect a jumper wire momentarily (< 10 seconds) to the A+ and F terminals of the plug. If voltage increases above 14-14.5 volts, replace regulator, if not, replace alternator.

This assumes that you've followed everybody elses' advice and check continuity of all the wiring.

Note that I have seen some idiot lights glow dimly and charging systems show some output but have 1 diode in the pack gone bad.

BTW, the ALT idiot light is powered by a feed from the ignition switch, before the resistor wire connection to the lamp, and then from the lamp through the harness and firewall connections to the I terminal on the regulator. A short to ground between the lamp and the regulator will light the lamp too.
 
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