I have a 1985 f150 302 and one day I tried starting the truck and turned the key all they way and it wouldn’t crank over I had power to my headlights and dash as well as radio but still wouldn’t start I took off the starter and had a shop test it for me and it worked perfectly I even tried to bypass the solenoid on the fender to send power to the starter still nothing I checked the ignition swicth saw it had been separated and replaced it with a new one now when I turn the key it still doesn’t crank over and shows the brake light indication whenever I try to start it and my parking brake is off I don’t know if it’s my solenoid or what anymore please help what should I do?
Check the ground end not on the battery.
Have you at least used a test light or DVOM (digital volt ohm meter) to see of you have power to the solenoid???
And like Barkydog said, check your grounds also…
Could it be the neutral safety switch associated with the shift lever?
Try banging on he starter with a hammer and then see if it starts.
If it does, the brushes in the starter are worn.
Tester
If indeed there’s no power to the starter, wouldn’t the problem be upstream of the brushes?
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Update I have used a voltmeter and have 12 volt constant and no power 12 volt cable to starter (this is with key on) I have bypassed the solenoid and starting to get a crank but it is faint and it feels like it doesn’t have enough power I have check my ground (as suggested) that leads to starter and found that it is cover in oil (classic 302) and you can see it bent to the point where it shows bare wire I’m getting fairly certain it might be my ground due to the loss of power
Sounds like your negative battery cable is corroded. The pickup is definitely old enough to need a new one. Check where one lug on the cable is attached to the fender also. It gets rusty on the fender. If the insulation on that cable is cracked everywhere then it’s no good.
A good test is to attach a jumper cable from some metal on the engine to metal on the fender, with another one from engine to negative battery terminal. That should work when you turn the key to start it.
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I have an older Ford truck. Don’t know if it is configured the same as yours. I’ve had to replace the starter solenoid once, and another time the solenoid’s ground wasn’t making a good connection to the chassis.
This is a difficult experiment to do correctly. You probably have some high resistance connections causing the weak start. suggest to discontinue that approach, and use the starter solenoid to crank the starter. that method, you’ll have good low resistance connections. If it wont crank that way, either the starter solenoid is faulty, or the starter is bad. With key in “start” what voltage do you measure at the starter power input terminal, probe voltage from terminal to starter case.
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Yes the switch solenoid is critical too. I neglected to mention it. If it doesn’t clack when the switch is turned then it may be bad or attached to rusty metal. Thanks to GSJ.
Isn’t the ground for the starter solenoid provided by the neutral safety switch?
My truck doesn’t have a neutral safety switch. The ground is provided by the fasteners that bolt the solenoid to the firewall.
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The heavy solenoid part grounds to the fender/chassis. The switch part runs the current to make the starter work. Lots of switches here.
Update again I have no power from s wire terminal solenoid from when I turn key that is what stopping the solenoid to lead power to starter I want to have the truck turn on by the key but I don’t know if it’s either due from ignition swicth or the universal locking key tumbler any advice the starter works perfectly fine and grounds are good
Are you turning the key to ON ?
or
Are you checking while someone else turns the key to START?
On my older than yours Ford truck the starter solenoid has an “s” terminal and an “i” terminal. The “s” is an input to the solenoid, coming from the ignition switch. The “i” is an output from the solenoid, providing extra high power to the coil, but only during cranking.
Yes I had the key on even had a voltmeter to test if I was getting anything and had no volts had somebody behind the wheel turn over and over and nothing what could the s wire be grounded from?
Can’t speak to OP’s specific f150 starter circuit configuration, but on my older Ford truck IIRC I can crank the engine using a jumper wire from battery positive to the “s” terminal on the starter solenoid.
Being a 1985 version, OP’s F150 probably doesn’t have the “i” terminal on the solenoid to boost the input voltage to the coil during cranking. That method is mostly used with conventional ignition systems; OP’s truck probably has electronic ignition.
If jumping the “s” terminal causes engine to crank, problem is likely either the ignition switch or transmission/clutch safety switch. Less likely, problematic fusible link. Note that jumping s terminal may not be advisable for some starting circuit configurations.