Help needed with troubleshooting saftey switch

[RickKlem]

Originally Posted by timmy2

Brown/black on '77 body harness comes out below the rear 14 pin connector.
Tach and CDI power are in the "T" connector for '77
Refer to my earlier posts.
Need to know how the engine swap wiring was done.

Find the single brown/black wire below the 14 pin connector, ground it and see if the fuel pump stops.

Dennis and Tony,

Sorry I have been MIA , Work has me busy and out of town for the next 2 or 3 weeks. I did have time this morning to check from 85 to the pin on the rear AFS and there is a break somewhere. I just seen all of the post since my last post and I will tried to find time to verify the connections at the rear. I need to go back and check my notes when I did the swap but I did use the harness from the updated 81 3.0L. I believe that I spliced it into the body harness . Again, I will try to check it when I get home tonight. I fly back out of town Sunday for two more weeks on the road.

Thanks
Rick

[RickKlem]

I am back in town for a few days so I was able to spend some time on it and here is what I know.

The brown wire coming from pin 85 on the FR to the rear is not plugged into any thing.



And the wire(s) , white plug, coming from the AFS switch which I found on the 81 3.0.L harness is below. I have the red wire going to a switch 12 Volts and the brown wire to nothing.

I checked the AFS with an ohm meter and it checks out good as expected when I lift the plate.
Could I connect the brown wire on the white plug below to the single wire in the above picture? Then leave the red wire connected to the 12 volt switched or do I need to connect it to some where else?


Thanks
Rick

[ossiblue]

Originally Posted by RickKlem

I am back in town for a few days so I was able to spend some time on it and here is what I know.

The brown wire coming from pin 85 on the FR to the rear is not plugged into any thing.



And the wire(s) , white plug, coming from the AFS switch which I found on the 81 3.0.L harness is below. I have the red wire going to a switch 12 Volts and the brown wire to nothing.

I checked the AFS with an ohm meter and it checks out good as expected when I lift the plate.
Could I connect the brown wire on the white plug below to the single wire in the above picture? Then leave the red wire connected to the 12 volt switched or do I need to connect it to some where else?


Thanks
Rick

Without rereading the entire threat, let me offer this.

Assuming the wire in your first picture is from terminal 85 of the FR, it needs to be connected to the AFS switch wire.

Before doing that, however, put a test light on the white terminal connector to the brown wire to check if it is grounded. Then, lift the sensor plate in the intake. Does the brown wire lose ground connection? If so, connect the wire from 85 to it. If not, do not connect to it as it is a constant ground and the relay will never cycle into the running position.

[RickKlem]

Originally Posted by ossiblue

Without rereading the entire threat, let me offer this.

Assuming the wire in your first picture is from terminal 85 of the FR, it needs to be connected to the AFS switch wire.

Before doing that, however, put a test light on the white terminal connector to the brown wire to check if it is grounded. Then, lift the sensor plate in the intake. Does the brown wire lose ground connection? If so, connect the wire from 85 to it. If not, do not connect to it as it is a constant ground and the relay will never cycle into the running position.

Ok, I will try that , but meantime what should the red wire from the AFS be connected to? Will any switched 12 volt work?

[boyt911sc]

Originally Posted by RickKlem

Ok, I will try that , but meantime what should the red wire from the AFS be connected to? Will any switched 12 volt work?

There is no red wire going to the AFS switch. The switch has two (2) brown wires. The orientation of the 3.0 liter SC AFS switch is as follow:

Driver side (cyl.1-2-3) has brown/red wire going to the wire plastic connector (engine side). And the chassis side for this wire (brown/black) goes to FP relay terminal #85.

Passenger side (cyl. 4-5-6) has brown wire going to alternator @ D-.

Use a test light or continuity tester for troubleshooting or identifying these wires. This is basic electrical 101.

Tony

[boyt911sc]

Originally Posted by RickKlem

I am back in town for a few days so I was able to spend some time on it and here is what I know.



Thanks
Rick

Rick,

This is the picture of the white electrical connector for the engine harness built by Dennis P. Take note of the wire color (chassis side) and from the engine harness.



Engine harness:
Red wire @ white connector goes to CDI @ terminal #15.
Brown/red (actually it is pink/red; ask Dennis) @ white connector goes to AFS switch pin (driverside or cyl.1-2-3).

Chassis harness:
Red wire @ white connector goes to ignition switch @ terminal #15.
Brown/black wire @ white connector goes to FP relay socket @ terminal #85.

NOTE: The above is for an SC engine and chassis. Since you are using a '77 chassis, the chassis side would be slightly different as mentioned by Dennis. I have a '77S chassis that I will install this motor (shown in the picture above). But I have not yet looked closely at the chassis. So I will be doing this exact work in a few weeks.



So if you could document with some pictures the location of the brown wire from the FP relay and red wire from the ignition switch would help other readers including myself. My '77S chassis is stored a few miles away from home.

Tony

[RickKlem]

I will try to say this differently.

This is a picture of the wiring harness on the 3.0L engine side. About five inches below the 6 pin CDI plug is a two wire white plug. That plug has a brown wire with what looks to be a small red stripe and a solid red wire. Using a DVM I checked for continuity from the red wire at the plug to the connector that plugs into the AFS on the passengers side (4-5-6) and I have continuity . Then I checked the brown wire on the same white wire to the plug for the AFS drivers side pin (1-2-3) and I have continuity. So I am very confident that the white plug and wires below enter into the engine wiring harness and terminate at the green AFS plug.

Note: I replaced my CDI with a MSD AL6 some time back. The red wire that you see spliced into the red wire at the white plug goes to a switched 12 Volt source and to the MSD to provide switched 12 Volts.



Then the picture below is the rear area of the fuse and relay mounts. I unplugged the 14 pin connector so that you can see the single brown wire with a black plug on the end. This is original to the 77S and it goes to the pin 85 on the FR.

Note: In order to make my AFS work again I was trying to confirm:
1. IF I were to connect the brown wire seen in the above picture coming out of the engine wiring harness which is from AFS pin on drivers side (1-2-3 cylinders) to the brown wire seen in the picture below that terminates at pin 85 FR, would that work?
2. Should I connect the red wire in the above picture which is the AFS passenger side (4-5-6 cylinders) to a switched 12 volt source as I currently have it?

Tony , you mentioned connecting this to the Alternator @D- , but I have no idea where to start to find this wire or connection and I don't want to rip my wiring harness open and start pin poking my wires to find it. If I need to connect this wire there instead of the switched 12 volts, could you please at least give me a hint to where I could find this wire to Alternator @D-????


I don't mean to sound frustrated , but what I have and what is in the pictures that you posted don't match and I don't know if it is because they are different years modules or if I am looking at the wrong plug on my end.
Thanks for any help
Rick

[ossiblue]

You need to confirm if the brown/red stripe wire in the double white connector loses ground when you lift the air sensor plate in the intake. That is the key to the safety switch/relay circuit--the loss of a ground to terminal 85 when the air flow sensor plate raises from its stop.

Run a quick test to see if the brown/red stripe wire loses ground. Use a test light with the wire as the ground connection. Lift the sensor plate and if the light goes out, that is the wire to connect the lead to terminal 85.

[RickKlem]

Originally Posted by ossiblue

You need to confirm if the brown/red stripe wire in the double white connector loses ground when you lift the air sensor plate in the intake. That is the key to the safety switch/relay circuit--the loss of a ground to terminal 85 when the air flow sensor plate raises from its stop.

Run a quick test to see if the brown/red stripe wire loses ground. Use a test light with the wire as the ground connection. Lift the sensor plate and if the light goes out, that is the wire to connect the lead to terminal 85.

I tested it and it does lose ground when the plate is lifted. So I will connect this brown wire to the single wire that goes to the pin 85 FR. That leaves the other red wire. Does it matter where it connects to? Tony mentioned the Alternator @D- , but I don't have a clue where to find this connection or wire to splice into

Thanks
Rick

[boyt911sc]

Originally Posted by RickKlem

I tested it and it does lose ground when the plate is lifted. So I will connect this brown wire to the single wire that goes to the pin 85 FR. That leaves the other red wire. Does it matter where it connects to? Tony mentioned the Alternator @D- , but I don't have a clue where to find this connection or wire to splice into

Thanks
Rick

Rick,

What ever you do, DO NOT supply power (12 volt) to the AFS switch!!!! The AFS switch is a ground contact with BROWN wires. I have to go over and re-read your post about the RED wire going to the AFS switch (?).

Summary:
FP relay terminal #85 wire goes to the white connector (chassis side). The engine side white connector with brown/red wire goes to the pin (cyl.1-2-3 side) at the switch. The other pin @ cyl.4-5-6 side goes to D- (alternator).

Consider talking to LJ. He could explain it better than anyone around. I discovered the anomaly in Dennis engine wire harness with a reverse wire installation. Which would be no problem for engines with plastic fuel lines but would cause a malfunction for engines with metal fuel lines ('81~'83) SC USA models. I believe he has corrected the problem already for the new harnesses.

Tony

[timmy2]

Let's see... I have told you what to do, others have steered you all over the place.
This is so simple.
I have built multiple new engine conversion harnesses for exactly what you have.


Connect the brown/black coming out of the body harness to the Brown/red coming out of the engine harness in your photo with a jumper to make your flow switch work.
Done.
Don't mess with any other wires.
Sorry, I'm tired and a little grumpy...

Just install the he jumper and give it a try.

[timmy2]

Originally Posted by RickKlem

Could I connect the brown wire on the white plug below to the single wire in the above picture? Then leave the red wire connected to the 12 volt switched.

Thanks
Rick

Yes, do this.... nothing else...

[boyt911sc]

Dennis,

I will be installing an SC engine into a '77S roller pretty soon. The roller is stored away from home and it is raining now in Philly area. In the white plug shown in the picture below has 2 red wires and a black (?) wire.



What is the black wire for? Is this a black wire with violet stripe on it? Thanks.

Tony

[timmy2]

Hi Tony,
Yes, the second wire on the '77 2 wire "T" connector, near the CDI, is the tach signal connection.
It is black/purple.
The brown/black air flow safety switch wire is near/below the male 14 pin connector.

[boyt911sc]

Originally Posted by timmy2

Hi Tony,
Yes, the second wire on the '77 2 wire "T" connector, near the CDI, is the tach signal connection.
It is black/purple.
The brown/black air flow safety switch wire is near/below the male 14 pin connector.

Dennis,

So to utilize your SC engine wire harness (for white connector) do I need to:

a). Remove the black/violet wire (from the '77S white connector) and install the brown/black from FP relay terminal #85?
b). Connect the black/violet from tach to black/violet of CDI @ TD?

I know that the white connector from engine (using your SC harness) needs two (2) wires.
a). Brown wire from terminal #85 (FP relay socket).
b). Red wire from ignition switch @ 15 to power the CDI.

What do you recommend to your clients when they do this conversion (SC engine to '77). BTW, I got two (2) sets of engine wire harness from you. So I consider myself one of your clients too. Thanks.

Tony

[timmy2]

Hi Tony,
Normally I wire the harnesses for the customer so they are plug and play when installing a 3.0 with 6 pin CDI.
You need to Re-wire the 3.0 14 pin female plug to the "77 configuration.
Run the tach wire from CDI to purple black.
Run the brown/red on engine harness to the brown/black single plug.
I just happen to be building a '77 through body harness this week so I can give you a 14 pin male plug layout for the '77 later when I am at home.

Cheers,

[boyt911sc]

Originally Posted by timmy2

Hi Tony,
Normally I wire the harnesses for the customer so they are plug and play when installing a 3.0 with 6 pin CDI.
You need to Re-wire the 3.0 14 pin female plug to the "77 configuration.
Run the tach wire from CDI to purple black.
Run the brown/red on engine harness to the brown/black single plug.
I just happen to be building a '77 through body harness this week so I can give you a 14 pin male plug layout for the '77 later when I am at home.

Cheers,

.
Dennis,

I have made a chart for the SC and '77S 14-pin connectors in the 90's. However, the '77S chart has not been used as reference yet. If you could provide a copy of your '77S 14-pin would be great. BTW, I will be needing a new set of engine wire harness for a '83 this summer. Thanks.

Tony

[timmy2]

'77 male 14 pin pin out:
1. Yellow starter solenoid
2. Green spare for manual trans
3. Green/Black Oil temp
4. Green/Red oil pressure gauge
5. Green/Yellow reverse switch from fuse panel
6. Grey/Brown reverse switch to 6 pin lights
7. Blue/yellow spare on manual trans
8. Brown/white spare
9. Green/White oil pressure idiot light
10. Red/White for WUR, AAR etc. from front fuse panel.
11. Blue alternator light.
12. Blank (no wire)
13. Yellow/Black engine blower motor relay
14. Red from alternator B+ goes to 3 Fuse panel. (Fuse 3)