[micken]

we shorted out the battery cables in my 1968 nova because one touched the exhaust. We changed those, got a new battery, had the strter and the cilonoid tested, and changed the fusilage connectors, but nothing works still. I was wondering if anyone has any idea what else might be wrong?

[red65mustang]

test with a volt meter that you do have 12V on the "S" terminal on the solonoid when the key is in the start position

no volts?
key off, secure one end of a jumper wire to the "S" terminal,
touch the other end to batt plus,
solonoid engages and starter cranks (you bypassed all the car wiring and proved the solo and starter are happy).....

probably a burned/bad "S" wire to the ign switch and or bad ign switch

[docvette]

Doc here,

Is the whole car dead (no lights, no horn, no accessories), or is just the starter not functioning?

If you have lost power to the whole car, look for an added fusible link to the wire (10 gauge) coming from the big post on the starter solenoid to the car's wiring harness. Vehicles of that vintage did not have them factory stock, but it may have had it added.

If you have no fuse Link, and the 10 gauge wire did not burn open, or the rest of the car has power..

Locate the neutral safety switch. Unplug that switch, and jump across it .. Try the "Start" function..If it works, you have burned the neutral safety switch out..Replace as needed.

If the system has integrity all the way back to the start switch, Check your engine grounds, If your battery cable DOES not ground at or near the starter, you may have opened one of the wimpy ground straps the factory puts in on the engine mounts. BE sure you have good frame and engine grounds!!

Does the car crank when you jumper the "S" terminal to the Big bolt on the solenoid? Have you tried jumping the big bolt to the big terminal below it that goes into the starter motor? Does the motor wind up? If so power to that point is good.

If you have that you have an open wire between the starter solenoid main power or "s" terminal to the Ignition switch.

Doc

[micken]

Tested power to the starter by bypassing and it has power there. Someone told me to replace the ignition switch, but I can't seem to be able to remove the switch.

[37ford4dr]

Originally Posted by micken

Tested power to the starter by bypassing and it has power there. Someone told me to replace the ignition switch, but I can't seem to be able to remove the switch.

you need to spend more time touble shooting.....make sure you have power to the swich before you replace a fundtioning unit only to have hte same problem...get a test light and start testing the fuse panel and work your way through the ignition circuit....i would want to look closely at ( or for) the fusible links on the starter.

[docvette]

Doc here,

37FOrd4dr makes very good sense..before throwing parts at it troubleshoot the system first and narrow the field down..

First you did not answer the question: "is the rest of the electrical system working? lights Ect.." Very important in determining if your main feed to the power buss has opened up or not.

Next , Put a DVOM set for V X 50 or autorange on the "s" terminal, and have someone turn the key to start..If You see 12 volts in start that declines in "Run".. then the ignition integrity is good.If NOT...

Locate the neutral safety switch. Unplug that switch, and jump across it .. Try the "Start" function..If it works, you have burned the neutral safety switch out..Replace as needed.

retry the test at the "S" terminal.

Just jumpering the big battery terminal to the "S" terminal proves nothing except the battery is good and the starter and solenoid works..It will not tel you if in fact the ignition switch is open or not..

The most common cause is neutral safety switch or an open on either the wire feeding the switch, or the "S" wire itself..

DOC

[red65mustang]

PVC wire insulation melts at only 170*,
easy for a batt short to melt the "S" wire and make a short in the harness, fair to good chance your switch is still good

do you have a volt meter?,
a inexpensive Sears or Radio Shack meter is fine for this...Harbor Freight is $20? buy a pack of alligator clips to make jumpers also

test the ign switch, (and the neutral safety switch and the wires) before you pull parts

disconnect the battery first!
turn the meter to a 2k or so ohms scale (should read 1.000, touch the 2 leads, should read 0000)
at the switch, unplug the "S" wire, with one meter lead hooked to a good ground, the other hooked to the "S" plug on the switch, turn the key to start position

meter reads 0000, switch is fine,
meter reads 1.000, double check your connections to the meter, still 1.000=bad switch

BE SURE! THE TIRES ARE BLOCKED! SO THE CAR CAN'T ROLL! to test the neutral safety switch, this time put a lead in each of the unplugged 2 wires to the switch, meter on ohms, car in park or neutral should read 0000, in drive/reverse/low/etc should read 1.000(starter can't crank when driving)

test the wires, disconnect and/or unplug both ends of a given single wire, one lead clipped to one end, other lead touched to the other end (with a jumper to reach if required) on ohms scale, 0000=good wire, 1.000=bad wire

meter doesn't go to full 0000 on a switch or wire= corrosion usually, or about worn out

using a volt meter ain't rocket science when testing for is it good or bad

you didn't answer the question, are the headlights working or is everything dead...interior lights, radio. etc

[micken]

nothing elctrical in the car works, lights, horn, or anything. where does the "s" wire hook into the elctrical chassey? Does it go directly to the ignition switch?
We did a voltage check with the "S" terminal with the key in start, and there was no power.

[docvette]

Doc here,

Originally Posted by red65mustang

turn the meter to a 2k or so ohms scale (should read 1.000, touch the 2 leads, should read 0000)
at the switch, unplug the "S" wire, with one meter lead hooked to a good ground, the other hooked to the "S" plug on the switch, turn the key to start position

meter reads 0000, switch is fine,
meter reads 1.000, double check your connections to the meter, still 1.000=bad switch

If I read this post correctly, and I think I did..If you do this test as outlined, AND the Ignition Switch has power to the main feed..AND the Contacts DO work, when you hit Start..

Your meter will make a loud pop..and emit a large amount of smelly smoke..you will destroy the Ohms scale of the meter..Or (if fused) blow the meter input protection device.

You can not measure between the "S" terminal Ignition switch and ground , on an Ohms scale..IN Circuit (hooked to the Ignition Switch)

The Ignition is feed from the battery, "HOT AT ALL TIMES" and distributes power to the selected Contacts.."RUN", ACC", And "START"..Ground is NEVER switched through the Ignition Switch.

The only way to measure a Wire or Component In an Ohms Environment , In the presents of power, Is to isolate the wire or component from that circuit..(disconnect it at both ends, and measure end to end)..

The scale you want is Volts, V X 50 or auto range..

Anyway, The "S" wire goes from the :

• Starter solenoid "S" terminal to:
• The Neutral Safety Switch located on the transmission or Column Linkage to:
• The "HOT IN START" terminal on the Ignition switch.
• IF the car is a factory manual transmission, It may also have a Clutch Over ride switch located on the Clutch pedal.

However, If the car is totally Dead..

The "S" wire IS NOT your problem.

You either have a BLOWN Fusible link or Maxi Fuse that somebody installed aftermarket, (Pre 70 GM did not have Links)

OR the 10 Gauge wire coming from the BIG BOLT on the Solenoid Terminal where the battery cable ties in, is open to the Vehicle Fuse Buss..(meaning the IGNITION switch IS NOT getting "HOT AT ALL TIMES" feed from the starter solenoid battery connection.) This is also where a Fuse link should be installed , at or near the starter solenoid..

That being said, The next logical deduction is the power that is missing from the "HOT AT ALL TIMES" at the Ignition switch, Is not going to the "HOT IN START " function of the same switch..

You need to abandoned the search for missing power on the "S" wire and start tracking down the lost power from the solenoid battery terminal (10 gauge wire) back to the car ignition switch, or fuse link along the way. A Fuse link may be located at either the starter solenoid Battery cable, Or at the horn relay, Or at the BATT terminal of the voltage regulator. (if externally regulated).

Find and repair that wire, and the Car will operate Fine electrically.



Doc

[red65mustang]

micken,
doc's right,

I forgot to tell you to disconnect the battery before you ohms test the ignition awitch