Peter Zimmermann

Edward: For some reason I completely missed this thread, but I might be able to help. Your terminal 50 (yellow) wire is part of a harness that has a 5-pin firewall connector just above the ignition switch. Be sure that the connector (it's round, black, and about an inch in diameter) is seated properly. If that's OK, go under the trunk, pull back the carpet behind the brake booster, and locate the yellow wire at a male/female clear, in-line connector (you might have to remove the air control paper hose on the driver's side). Make sure that connection is tight. Now, you'll have two branch wires (the main yellow wire is 4mm) that are each .5mm; one goes to the A/C relay in the smugglers box, one goes to the heater system relay in the engine compartment, I think. When you crank the engine, current travels to both those relays, and shuts off the A/C, or heater, if one of the systems is on, which maximizes starter strength. Open your smugglers box, locate the A/C relay on the passenger side wall (it's mounted on a small stud using a nut), disconnect its wires and try your starter (obviously the starter system must be entirely assembled/connected). If the starter works the problem might be the A/C relay, or it might be the branch/connector where the two small diameter wires leave the large, yellow wire - I'm not sure where in the car that happens, but it might be at the male/female connection near the driver's side (left) trunk lid hinge. If the problem is unchanged, locate and disconnect the main heater relay in the engine compartment and try it again. Good luck!

Another thing that can cause the same problem is if your car has ever had an aftermarket alarm system, and that system has been disabled but some of its components are still in the car.

Edward1

Hi

Thank you so much for replying to my post, I will surley look into the information you sent. I started tracing this wire you are talking about but it is so compact that it is hard as I'm sure you are aware of to trace wires, but now with locations to spot check hopefully this wil help.


Thanks again
Edward

Edward1

Hi


Peter, this morning I went through the information you sent. Here is what I find. There is a bundle of wires adjacent to the brake booster with the yellow wires as you indicated in a clear plastic plug-in connector. All seem to be alright and pluged in tightly. My next step was to check the relay in the smuglers box. It appears that the relay may be bad since that at the plug in connector is melted at the red/white wire. I opened the relay and the diode is popped out from what appears heat or high voltage, I didn't run a check on the diode as of yet.

There is 12V constant at the red wire, the black wire also has 12v, the yellow gets has no voltage. You mentioned that if the relay was unpluged it should start, so I unpluged the relay and tried, but still no starting. I would have checked the relay in the engine compartment, but can't seem to locate it at the drivers side in the engine compartment. When checking under the car the yellow and red wire from the starter and solonoid appear to go into the engine compartment near the passenger side of the engine, but can't trace it from there.

Would it help to remove the fuse for the ac and heater to test?

Thanks for the help!


Edward

Peter Zimmermann

Edward:
1. Can you have someone turn the ignition switch to "crank" and check the large yellow wire near the booster for power?
2. Then, can you do the same at the yellow wire at the relay in the smugglers box.

I don't think that pulling fuses will do the same thing, because the crank voltage enters the relay regardless. The central heater relay is one of the silver boxes in the engine compartment, left side. If your heater blower works in the engine compartment, unplug one box at a time to see if the blower stops. If the blower's bad you can always use a test light on the blower wire. With the ignition switch in crank position the yellow wires should all be hot...

Because you stated that you only had .7v at the solenoid wire we're hoping that voltage from terminal 50 (yellow wire) is being diverted, and the A/C and heater relays are the prime suspects.

Edward1

Hi


Peter, here are the results of the test that I have ran. With the ignition switch in place I get .7 volts at the connection at the brake booster. No voltage in the smugglers box on the yellow wire as well as at the rear engine compartment. So my next step is to start the engine without the ignition by jumping across contact point 30 and 50, starter spins. Next test is a ran a continutity check from the large yellow wire on the ignition switch and the wires at the brake booster and get continutity. In my opinion I have a bad ignition switch. The ignition is a complete unit I purchased a while back from Pelican parts, the first one they sent was damaged and after a few words with them and several weeks later they sent another one. I have not taken apart the new one to test it. When I am jumping across pin 30 and 50 to me this proves that the ignition switch is faulty. What do you think?


Ed

Peter Zimmermann

I think that your conclusion is correct. If you're confident that your wire bundle at the switch is corrosion-free, and that all the wires are in the correct positions, I can see no other reason for your problem based on this most recent post. I might add that I've never run across a faulty new ignition switch, that's terrible luck!

84_Carrera

Guys, I was getting the same .7 V at the starter (& 14 pin connector) with the "bad" switch, FWIW. I'm still having the old "bad" switch just hanging under the dash & using the phillips screwdriver to turn her over successfully. Tucked in the dash, no-go.

FYI.

Brads911sc

I have exactly the same problem with my 83 SC. I have an electronic ignition on order as well as a new starter and a new transmission ground strap...

Brads911sc

Thanks Peter. I am glad you responded. I will take a look at these items tomorrow....

Edward1

Hi

On all wires and connections on my car all contacts have no corrosion, rust or any other residue on any contact checked. Would it be possible that the switch I ordered is not a correct replacement???? Someone mentioned that they had a battery that showed the right voltage, but didn't have the amperage to start the engine, but then the battery will turn the engine over real good so that kind of throws that idea out. What is so fustrating is that all checked indicates no problems, but still not working. I had so much problems with Pelican getting them to send another ignition switch and housing ($539.00 +/-) when the first they sent was damaged, I can about imagine what their thoughts will be on my returing this part.
If anyone can think of any other thoughts on the matter, please let me know.


Thanks

Edward

Brads911sc

Edward, If you did have a bad switch, wouldnt it be the electrical portion? In that case, couldn't you just buy the $60 electrical switch available on just about every website I have looked at? I had a similar experience with Pelican.. I use Foreign Intrigue, the Parts Bin, Drivewire, ZIM, GPR, before I go to Pelican. I did a search and I couldn't find anyone else who even sells the entire $550 unit you purchased. That means to me that it must be rare for it really to be bad. Between your old one and the new one, you should be able to purchase another electrical unit and try it with either full switch. I am going to dive into mine today. I have the same problem.. but I'm just starting my assessment. Haven't done much more than check voltage at certain places. Question, I have a pretty complicated digital diagnostic tool for electrical. Is there a way to actually check the relay with it off the car and determine if its bad?
Let me know how it goes...

Brads911sc

Ok.. Here is my update.. Please weigh in Peter...
1. I have power at the Relay in smuggles box.
2. I have Power at the relay at the Fan Relay in engine compartment.
3. I do not have power at the fat yellow wire at the starter.
4. I have a constant power at red and black at starter.
5. Doesnt make a difference if I swap out the relay at the Fan Relay. Also doesnt do anything if i unplug it. If I unplug it.. wouldnt I need to jump the pins? I dont think its this because I tried a known good relay.
6. Doesnt make a difference if I unplug the relay in the smugglers box. Should i jump the wires in some way to bypass the relay?
Other plugs seem to be tight.
I have a AC relay on order. Have the electronic ignition switch on order.
Seems that if I get power at the relays its probably not my ignition switch.
Im guessing the AC relay? or a Bad wire from the Fan relay to the starter?
Am I on the right track?

Thanks
Brad

Edward1

HI

I am not sure if there is a way to test the switch itself, but it would seem to me that since if take the switch off of the harness with the one inch plug still plugged it that when I jump across pin 30 and 50 that by testing at those same points across the switch itself I should get continunity which I don't. When I use a jumper across pin 30 and 50 of the harness and place my ohm meter at the harness in the trunk where the yellow wires meet and go to the smugglers box relay I get 12 volts, so this tells me that there is something not right with the switch. No, I don't need to purchase the whole assembly, but I am reluctant in spending more money until I am sure of what the problem is. The folks at Pelican parts are amatures trying parts that they have no knowledge of what they are selling and how they work. I have always bought my parts from P.A.P Porsche parts and have had real good service and advise. They were out of stock of the switch I wanted and ended up at Pelican. Big mistake.


Thanks for the input

Edward

Peter Zimmermann

Brad: I'm not really clear on your post, but I'll assume that your SC has factory A/C. The fan (engine compartment heater blower) relay is not a factor in your car - the Carrera heating system is different. I don't remember, but I don't think that your A/C relay plays a part either, at any rate if it did it would only cause a voltage drop, not complete interruption of power.

Now, let's move to your yellow wire on the solenoid - it should only be "hot" when the ignition switch is turned to "crank" position. If you have no power, you have to look for the yellow wire connection behind the brake booster. It will be a male/female in-line connection, check there for power, also with the ignition switch in crank position. If there is no power at that connection, check the bulkhead harness connection above the switch, as described for Edward. If you have power at the male/female connection, you have to go to the 14-pin connector in the left rear corner of the engine compartment and check for corrosion... This should get you going in the right direction.

Brads911sc

Thanks Peter. Ill send an update.