1999 Ford F150 Starting Voltage Low

1999 FORD F-150
175 MILES • V8 • 2WD • AUTOMATIC
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TERRYDURHAM
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When turning the ignition key to start the vehicle, the voltage to the coil of the starting solenoid on the firewall under the hood only goes to 3.5 volts dc.

The voltage is the same with the wire removed from the solenoid coil. With the key not in the starting position, the voltage is 0.6vdc

The 50amp fuse #111 is good.

I can jumper from the battery terminal on the solenoid to the coil terminal and the vehicle starts and runs fine.

Any Ideas?
Jan 10, 2010 at 7:03 AM
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JACOBANDNICKOLAS
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Are you refering to a starter mounted or one on the inner fender? Does it look like this?


https://images.2carpros.com/forum/automotive_pictures/249084_a_1.jpg

If it is like the picture, have you tried to replace it? Let me know. Joe
Jan 11, 2010 at 10:33 AM
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TERRYDURHAM
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That solenoid(relay) appears to be good. I can jumper from the 12v post to the coil and it engages the starter properly. The problem is when turning the key, the voltage to the coil terminal at the solenoid only reaches 3+ volts. Not enough to close the contacts of the solenoid.
Jan 11, 2010 at 10:48 AM
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JACOBANDNICKOLAS
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Have you replaced the solenoid? Have you checked the ignition switch?
Jan 11, 2010 at 1:24 PM
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TERRYDURHAM
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I have not replaced the solenoid, since it appears to be working fine. Is the ignition switch mounted on steering column, under the dash?
Jan 11, 2010 at 3:02 PM
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JACOBANDNICKOLAS
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Yes, it is on the steering column.
Jan 11, 2010 at 4:08 PM
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