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Help please, After 30 hours of searching the board and online I still have not found the proper way to wire the rpm and timing sensors into the main wire harness. Each sensor has a black wire or blue wire that is insulated for about one inch behind the plug then it turns into a bare wire going into the sheathing. The other two wires are yellow and a fully insulated black wire. On a Spider parts car I have that had one half decent connector plug I was able to determine that the yellow wire was in the middle of the plug and that it connected to the brown wire in the main harness. The main harness for both the upper & lower sensor plugs has three wires, white, brown, and black/bare. So, This is how I have wired up both sensors to the grey & black connector plugs on the main harness. The black/bare or blue/bare wire from the sensor hooks to the black/bare main harness wire..the yellow sensor wire hooks to the brown main harness wire.. the fully insulated black sensor wire hooks to the white main harness wire. Can anyone please confirm that this is a proper way to connect these wires????? Many thanks to Papajam for taking his time to help me & sending a diagram. I'm waiting to confirm this so I can start both of my Spiders that I'm working on. I would hate to test my connections by trying to start the cars then watch my harness melt down or fry the computer. Both cars were running until I crumbled up the connector plugs and managed to disconnect the wires when cleaning the engine compartment on one of them and then turned around and crumbled up the connector plugs and disconnected the wires on my other car while trying to see how the wires connected.... Sorry to get long winded. Thanks, Chris
 

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best way to check is the plug on the harness to the ecu( ecu's ) go to papajohn for wiring diagrams, yes they are the same coulour on both sensors 1 goe's to the fuel ecu, the other to the igniton ecu, you can match them that way, are they just unplugged and you don't know what goes to what plug? then just plug the sensors in the harness plugs.. try to start it.. starts you are ok, if not just revers the plugs..50/50 chance and no damage will happen, the lower on I belive is the fi sensor, the upper one ignition.
 

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Discussion Starter #3
Thanks for your help. My trouble is with the wires in the male plugs that comes from the sensors. The plastic male plugs broke into pieces and the sensor wires became disconnected from the female half of the plug attached to the main harness and I don't know for sure how to reconnect them properly. The female half of the plugs are in good shape and I can see how the wires are wired into it and what color they are. Papajams diagram for a 82 Spider does not show the sensor wire colors plus it shows only two wires coming from the sensor. My Spiders were built, 5-88 and 4-89. My sensors have three wires. I am trying to find out which color sensor wire attaches to which color wire in the main harness. Both sensors do wire up the same way. The lower sensor being the reference point transmitter and the upper sensor being the rpm transmitter. Any help with this will be deeply appreciated. Thanks
 

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I am not aware of the wire colrs inside the moulded plugs. Perhaps if someone has a dead sensor they'd be willing to disect it?

(I'll check my stash of old parts - I might have a dead sensor. But I'm at work all day today and for the next few days so I may not be able to do that right away. If you don't get an answer soon then reply to this thread and that'll remind me.)
 

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the second photo here showing the plug and how the wires fit might give some orientation as to which goes where, if the colors are the same as yours?
I guess the larger black sheathed wire is a screen of sort.
http://www.alfabb.com/bb/forums/5794865-post1.html
 

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Thanks, If I don't find out how the sensors connect I will remind you. If I find out what I need to know I will post it & also let Papajam know so he can add it to his wiring diagrams.
 

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Spiderserie4, Thanks for your reply. I did see your pictures during my search. My female plugs on the main harness are wired just like yours with the bare black wire at one edge of the connector, brown wire in the middle, and the white wire on the other edge of the connector. Could you tell me the colors of your wires in the male part of the connector that comes from the sensors and how they line up with which color wire in the main harness connector? I hooked mine up with the bare wire to the bare wire, Yellow wire to brown wire, and the fully insulated black wire to the white wire. I'm 99% certain that is how they hook up but wanted to make sure before I try to start it. Thanks, Chris
 

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....Could you tell me the colors of your wires in the male part of the connector that comes from the sensors and how they line up with which color wire in the main harness connector?...
oops! I misread your post and thought you had bust the female plug!

aren't my pictures unfortunately (just got them off the BB) so couldn't tell you that as my spider doesn't have the 2 sensors, but the single crank sensor.
Dom
 

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So, the bare wire is normal? that bothers me, since it's under the leaky windshield washer bottle. I'll wrap it with electrical tape or something...and that was my pic that I posted a few months back.
 

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Electrical Shield to prevent interference signals to the sensor. BTW, second thought, the bare wire should be grounded, also. Sometimes, you can get a short in this, but not often. Depends on how it's rigged.
 

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Discussion Starter #13
Thanks Eric & all that replied. I see that I have it wired correctly. I'll fire the car up in the morning. I'll pass this color code along to papajam. Thanks again, Chris
 

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Discussion Starter #14
The cars started right up with no problems so I figure they must be wired correctly. Thanks to all for your help. I'll pass along the color codes to Papajam. I know everyone like pictures but as of yet I have not learned how to do much on a computer. 1 of my cars is the $2014 Grassroots race Spider that I bought off the board last month. There are pictures there in the add. Thanks again. Chris
 
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