My 69 died a few days ago while out for a test cruise. It was running fine then died. It is getting gas and turns over. Tested for spark and have none. Suspected the Pertronix III unit installed in my distributor. I have the Pertonix hooked up as they instruct; red/+ and black/- leads from Pertoxnix hooked to + and - posts on their supplied coil. Then a 12 awg wire from the 'ign' terminal on the fuse box to the + side of the coil to provide 12 volts to the Pertronix unit . Not sure how to directly the Pertonix so I decided to check for voltage on the feed wire at fuse box 'ign' terminal. No voltage at the 'ign' terminal. Not sure if that terminal is 'hot' all the time but I also checked with the key in run and crank positions, nothing. To double check my testing hookup I also tested the 'acc' terminal on the fuse box. It has 12.20 volts when the key is turned. So now I'm trying to understand why would the 'ign' terminal would not have full battery voltage present. I know it gets fed from the battery to the horn relay bus bar and then to the fuse box. All connections look good. How to further test? Thanks for any suggestions.
Another electrical failure- No voltage at 'ign' terminal on fuse box?
Tom pugh
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Ok. I have learned more on this fuse box. Forget what I said about the left side fuse holders being the power side. The outboard fuse holders on the box are the power clips. Inboards feed the listed item. So yes, the Pertronix can blow that fuse from the IGN tap, as it is tied in the system fuse holder on fuse box inboard side.
But first start by doing the Pertroix troubleshooting called out in these links. Second link has the voltage and restance checks. You will probably save time.
Troubleshooting for Pertronix Ignitor and Coil Installation
Pertronix Power, Ground & Voltage Testing 2016
TIf you want to prove out the Pertronix unit, get another 14 gauge wire. It has to be long enoug to get to the battery or horn relay buss screw. Add a 20 amp fuse and holder to the wire and use what it will take to secure it to battery or horn relay. Hard connect it to Pertronix lead and the horn relay buss screw. Insert fuse when ready to start engine. If engine starts and shuts down, check that new fuse. If blown, get another Pertronix unit. If engine continues to run and idle, Pertronix unit is good. Check to see if Turn/Backup fuse blew, after checking that turn signal and B/U lights work. If not, then the combination of items is too much for the 20 amp fuse.. Larger fuse not recommended. Suggest a relay added and its power be tied to the IGN tap. A new power source from the horn relay bus be added and use the power through circuit to power the relay.
Here is a relay diagram. Get a 30 amp relay from FLAPS. Terminal 87A will not be used in the circuit, if you go this route. Relay pulls less than an amp. What I read is Pertronix Ignitor may pull 15 amp with a coil on same circuit. Camaro coil is powered of the ignition switch run and start positions (unless you modified coil power source). So Iexpect electronic unit probly pulls less than 5 amps.
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But first start by doing the Pertroix troubleshooting called out in these links. Second link has the voltage and restance checks. You will probably save time.
Troubleshooting for Pertronix Ignitor and Coil Installation
Pertronix Power, Ground & Voltage Testing 2016
TIf you want to prove out the Pertronix unit, get another 14 gauge wire. It has to be long enoug to get to the battery or horn relay buss screw. Add a 20 amp fuse and holder to the wire and use what it will take to secure it to battery or horn relay. Hard connect it to Pertronix lead and the horn relay buss screw. Insert fuse when ready to start engine. If engine starts and shuts down, check that new fuse. If blown, get another Pertronix unit. If engine continues to run and idle, Pertronix unit is good. Check to see if Turn/Backup fuse blew, after checking that turn signal and B/U lights work. If not, then the combination of items is too much for the 20 amp fuse.. Larger fuse not recommended. Suggest a relay added and its power be tied to the IGN tap. A new power source from the horn relay bus be added and use the power through circuit to power the relay.
Here is a relay diagram. Get a 30 amp relay from FLAPS. Terminal 87A will not be used in the circuit, if you go this route. Relay pulls less than an amp. What I read is Pertronix Ignitor may pull 15 amp with a coil on same circuit. Camaro coil is powered of the ignition switch run and start positions (unless you modified coil power source). So Iexpect electronic unit probly pulls less than 5 amps.
I have already tested the Pertronix module removing the power lead from the 'ign' tap on the fuse box and wiring directly from the battery + post to the coil + positive side where the module's power lead is connected. However, I did not not insert a 20A fuse. Turned the key to start and the engine fired immediately. So I assume the Pertronix module is good. Had to pull the lead from the battery to get the engine to shut down. Also, the 20A fuse in the fuse box was not blown. Thanks for the relay diagram. Looks like I will need another source for switched ign power.
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Using the + terminal on the coil adds the Pertronix Ignitor amp load on the ignition switch contacts. Expect contacts in the switch to fail quicker. Use of a relay triggered by the IGN fuse box tap is the most logical way to keep the amp load off the ignition switch and on the current 20 amp fuse.
You can test the relay on the IGN tap by wiring the 87 terminal to the tap and provide a good ground to terminal 85. Turn on the ignition switch. If fuse does not blow, you have a good trigger circuit. Then it will be to find a good spot under the hood to mount the relay. I suspect above column area would be right to keep wires as short as possible, with power lead coming from horn relay buss terminals then to the Ignitor unit.
You can test the relay on the IGN tap by wiring the 87 terminal to the tap and provide a good ground to terminal 85. Turn on the ignition switch. If fuse does not blow, you have a good trigger circuit. Then it will be to find a good spot under the hood to mount the relay. I suspect above column area would be right to keep wires as short as possible, with power lead coming from horn relay buss terminals then to the Ignitor unit.
Exactly. That's how it should work.
I hooked up the relay per your directions and the engine started just fine. Tested the turn signal, right signal is fine, tired the left signal and the fuse blew, engine shut down. I was surprised the engine shut down becuase I thought the relay was now handling the Pertronix function. Why did it shut down? Is it safe to assume the problem is likely in the left turn signal circuit or is the Pertronix/coil amp load still fully on the ign tap? Suggestions on trouble shooting?
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Pull the light bulbs from the left pack and left tail lights. With turn signal lever in center, start engine. If engine runs, select left turn. If it shuts down you hve a dead sort to find in wiring. Pull connector for tail harness to body harness and try test again. If it shuts down then problem still not isolated. You still have front light harness and body harness.
Let's know what you get at this point.
Let's know what you get at this point.
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There is s simpler way with an ohm meter. Pull tail light bulb and parking light bulb. Pull the fuse that blows when left turn signal is used. Ground black meter lead to good clean body metal point. Meter should read infinity (OL). Using red meter lead touch the park light bulb socket terminal for the turn signal. It should read infinity. Repeat task on tail light socket. If either read anything but infinity, then that circuit is defective.
If you are on the tail light or park light circuit terminal in either socket, you will read some value of ohms. Marker lights and license plate light will give you that reading.
If you are on the tail light or park light circuit terminal in either socket, you will read some value of ohms. Marker lights and license plate light will give you that reading.
Easier way to use the Ignitor systems, do what it wants, LEAVE THE BALLAST RESISTOR and STOCK COIL in place and functional, leave spark plug gaps down to .035 maximum, and let it live.
The Ignitors ARE NOT performance ignition systems, they are simple electronic sets of ignition points, NOT an MSD.
The Ignitors ARE NOT performance ignition systems, they are simple electronic sets of ignition points, NOT an MSD.
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I happen to like Pertronix and have NEVER had a failure.
Whether points or electronic with ignition wire should not be on a fused circuit. The main power wire from the battery to the horn relay and the into the ignition switch is protected with a fusible link. So either your trigger #86 for your relay or your 12v power #30 is tied into your turn signal circuit that has a dead short.
If you wired in the relay as shown above with an inline fuse, see if it is blown. My guess is not. The trigger 12v, wherever that it tied to is most likely wrong and should be connect to the pink from the ignition switch or the ignition spade on the fuse box which are not fused.
Whether points or electronic with ignition wire should not be on a fused circuit. The main power wire from the battery to the horn relay and the into the ignition switch is protected with a fusible link. So either your trigger #86 for your relay or your 12v power #30 is tied into your turn signal circuit that has a dead short.
If you wired in the relay as shown above with an inline fuse, see if it is blown. My guess is not. The trigger 12v, wherever that it tied to is most likely wrong and should be connect to the pink from the ignition switch or the ignition spade on the fuse box which are not fused.
I understand. However, I believe the ign spade on the fuse box IS connected to the 20amp fuse for the turn signals/backup lights. If that fuse blows the ign spade is dead. I'm using the ign spade as the trigger for the relay and when the turn sig/backup fuse blows the engine dies.
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But it should not blow the fuse. It only blow the fuse when the engine is running and the left turn signal is used. Not blowing fuse when the right turn signal is used. That tells me that the left turn signal circuit is drawing more power (amps) than the right turn circuit causing the fuse the blow.
Fix the issue with the left turn signal circuit and live in peace.
Fix the issue with the left turn signal circuit and live in peace.
yes, thats correct. I will be running your diagnostic suggestions tomorrow to isolate the problem in the left turn signal circuit. thanks
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Not sure what year your car is but when I lost 12 volt ignition on the fuse box on my 71 it was the steering cable connector had slightly pulled apart on top of the steering column. This could also explain blinker issues. Worth a check for sure if I read the updates correctly.
I pulled the bulbs from the left side of the tail light harness. Hooked up ohm meter with good ground to body, reads OL. Tested the harness left turn signal socket green lead and got a reading. Decided to run the same test on the right side socket yellow lead contact, removed bulb and got an OL reading. With the bulb still removed from the right side socket, retested the left side socket green lead got an OL reading. So it appears the left side turn signal circuit is defective, but why does it test OL when the right side bulb is removed?
please see my update on your testing recommedations
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When you two figure it out, please share your procedure and the results.
Jim
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