Problem with wire between battery and solenoid?
11-08-2010, 07:25 AM
#1
1st Gear Member
Thread Starter
Join Date: Aug 2010
Location: NC
Posts: 133
Problem with wire between battery and solenoid?
On the 67 I am working on with a friend we are having some issues.
When you turn the key over nothing happens (has power but engine does not crank). However my friend much more knowledgeable than me put a screwdriver across the solenoid to "short it out" and then the engine turns over.
We ruined one solenoid a couple weeks ago (started smoking and eventually where the terminal was just melted off) and he thought the solenoid was either not made for a mustang or wired wrong. We got another one and looked how a 2nd mustang was wired and these did not appear to be the issue.
So with the second solenoid on there and it still does not turn over with the key but does when you put a screw driver across the solenoid terminals my friend thinks it may be a problem with the wire from the battery to the solenoid. The wire definitely is not as big as the other wire from the battery.
My friend is probably right but I just wanted to put it out here to see if anyone else had some ideas.
When you turn the key over nothing happens (has power but engine does not crank). However my friend much more knowledgeable than me put a screwdriver across the solenoid to "short it out" and then the engine turns over.
We ruined one solenoid a couple weeks ago (started smoking and eventually where the terminal was just melted off) and he thought the solenoid was either not made for a mustang or wired wrong. We got another one and looked how a 2nd mustang was wired and these did not appear to be the issue.
So with the second solenoid on there and it still does not turn over with the key but does when you put a screw driver across the solenoid terminals my friend thinks it may be a problem with the wire from the battery to the solenoid. The wire definitely is not as big as the other wire from the battery.
My friend is probably right but I just wanted to put it out here to see if anyone else had some ideas.
11-08-2010, 07:33 AM
#2
4th Gear Member
Join Date: Apr 2010
Location: NJ
Posts: 1,027
Problem is likely between the key and the solenoid. Make sure both small wires are properly connected to the solenoid. Get a volt meter, measure between the positive post on the battery to the small ground wire on the solenoid. Make sure you have 12 volts. Then move the volt meter to the negative side of the battery and measure the voltage the the other small wire on the solenoid when someone is turning the key.
11-08-2010, 07:47 AM
#3
6th Gear Member
Join Date: Oct 2006
Location: Cork, Ireland
Posts: 6,417
ya, here's the wiring for it (wrote it up once)
if you bridge 'S' connector on selonoid with the power cable from battery you essentially do exactly what the ignition switch would do when putting into start position.
If you have auto transmission it's 90% of all cases the Neutral safety switch.
Try to start in park, try in neutral. try wiggling the shifter lever a bit in both positions while you turn key in start position.
If that cures it the NSS is misadjusted. If that doesn't help check the NSS switch.
Theres a connector with two wires at the trans. one for reverselight (maybe) and one being the NSS. disconnect the wire and bridge the wires (connect one with the other) with a paperclip or so. if that cures it it is the NSS. if reverselights come on you are at the wrong cables ... :-D
Kalli
if you bridge 'S' connector on selonoid with the power cable from battery you essentially do exactly what the ignition switch would do when putting into start position.
If you have auto transmission it's 90% of all cases the Neutral safety switch.
Try to start in park, try in neutral. try wiggling the shifter lever a bit in both positions while you turn key in start position.
If that cures it the NSS is misadjusted. If that doesn't help check the NSS switch.
Theres a connector with two wires at the trans. one for reverselight (maybe) and one being the NSS. disconnect the wire and bridge the wires (connect one with the other) with a paperclip or so. if that cures it it is the NSS. if reverselights come on you are at the wrong cables ... :-D
Kalli
11-08-2010, 01:40 PM
#6
6th Gear Member
Join Date: Oct 2006
Location: Cork, Ireland
Posts: 6,417
maestro it is inline with ignition switch and seloind 'S' port
battery+ goes to ignition switch.
if you turn the switch it routes this 12V+ to a different cable (which in manual transmission goes straight to the starter selonoid 'S'.
The way the selonoid works that it needs to shift huge power from battery to starter. if you wouldn't have the selonoid, you would have the cable from battery to selonoid going all the way to the ignition switch and back. first of all it's costly and second the switch would be _massive_ ... so the selonoid simply connects the outer two cables (one to battery, the other to starter) at the time you have 12V+ at the 'S' port.
if it's manual transmission, you can check with voltmeter what voltage you're getting at 'S' port when key is in start position. If it's very low voltage or nothing then the wiring might be corroded (check connectors at firewall). If cleaning them up doesn't help then I'd check from the ignition switch back . i don't think there'sany fuses involved here.
So from switch 'S' connector. this should have 12V on start, follow the cable and measure from there
if automatic there is an additional switch inline. So it goes the same way as in manual, only that the NSS is right inbetween (if you'd follow the wires). I only learned from 2+2 (I don't have an automatic) that the NSS switch plugs in to the top of the firewall in engine bay. Nothing else seems to be on that cable. so check that connector and simply check what I stated above: disconnect the connector at NSS (this is on transmission) connect the two cables with each other (paperclip or wire or ...) and try again. if it resolves your issue the NSS is misadjusted opr faulty
battery+ goes to ignition switch.
if you turn the switch it routes this 12V+ to a different cable (which in manual transmission goes straight to the starter selonoid 'S'.
The way the selonoid works that it needs to shift huge power from battery to starter. if you wouldn't have the selonoid, you would have the cable from battery to selonoid going all the way to the ignition switch and back. first of all it's costly and second the switch would be _massive_ ... so the selonoid simply connects the outer two cables (one to battery, the other to starter) at the time you have 12V+ at the 'S' port.
if it's manual transmission, you can check with voltmeter what voltage you're getting at 'S' port when key is in start position. If it's very low voltage or nothing then the wiring might be corroded (check connectors at firewall). If cleaning them up doesn't help then I'd check from the ignition switch back . i don't think there'sany fuses involved here.
So from switch 'S' connector. this should have 12V on start, follow the cable and measure from there
if automatic there is an additional switch inline. So it goes the same way as in manual, only that the NSS is right inbetween (if you'd follow the wires). I only learned from 2+2 (I don't have an automatic) that the NSS switch plugs in to the top of the firewall in engine bay. Nothing else seems to be on that cable. so check that connector and simply check what I stated above: disconnect the connector at NSS (this is on transmission) connect the two cables with each other (paperclip or wire or ...) and try again. if it resolves your issue the NSS is misadjusted opr faulty
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