72 CSi wiring
- Thread starter Chris Reber
- Start date
A ground wire is never black they are always brown. If near the starter it may come from the 12:00 terminal and is hot when cranking, be sure it is taped off or bad things can happen.
That double black wire comes from your ignition switch to that spade connector and then goes to your diagnostic plug. It is the crank signal to your starter.
The female spade connector goes into a plastic sleeve, and on the other side is a male spade with a large gauge red wire and two small gauge white wires. The large gauge red one goes to the 6 o’clock position of your starter and actually gives the Crank signal to your starter. One small white gauge wire goes to the cold start injector relay to activate it. The other small white gauge wire goes to the computer to let it know you are cranking the Engine.
BMW discontinued the use of a black wire directly to the starter in the mid 70s and turned it into a black white wire. In the 80s they turned it into a black yellow wire.
They are very few black wires in the BMW schematic specifically you never want to connect one to ground as Chris stated.
Connecting the black wire to ground that goes to the tachometer coil and diagnostic plug will burn out your Wiring in the engine bay . Connecting the large gauge black wire by your starter will burn out your wiring in your dash..
Connecting the large Black wire at your battery positive terminal to ground will fry your entire car.
No black wires to ground!
I strongly suggest that you study the D Jet Wiring schematic and once you have a copy, I will tell you where they neglected to put the colors of the wires that are important to your connections in the Engine bay
It is the only time I have ever seen BMW connect a black wire to a red wire and two white wires in the same connection and not show the colors of the wires
It is at Junction 168 on the schematic for the engine that the problem exists. You will see Schwartz SW goes to the connection but no colors coming out of the connection. The large gauge wire is red. The two small gauge wires are white.
Be careful and ask lots of questions…
The female spade connector goes into a plastic sleeve, and on the other side is a male spade with a large gauge red wire and two small gauge white wires. The large gauge red one goes to the 6 o’clock position of your starter and actually gives the Crank signal to your starter. One small white gauge wire goes to the cold start injector relay to activate it. The other small white gauge wire goes to the computer to let it know you are cranking the Engine.
BMW discontinued the use of a black wire directly to the starter in the mid 70s and turned it into a black white wire. In the 80s they turned it into a black yellow wire.
They are very few black wires in the BMW schematic specifically you never want to connect one to ground as Chris stated.
Connecting the black wire to ground that goes to the tachometer coil and diagnostic plug will burn out your Wiring in the engine bay . Connecting the large gauge black wire by your starter will burn out your wiring in your dash..
Connecting the large Black wire at your battery positive terminal to ground will fry your entire car.
No black wires to ground!
I strongly suggest that you study the D Jet Wiring schematic and once you have a copy, I will tell you where they neglected to put the colors of the wires that are important to your connections in the Engine bay
It is the only time I have ever seen BMW connect a black wire to a red wire and two white wires in the same connection and not show the colors of the wires
It is at Junction 168 on the schematic for the engine that the problem exists. You will see Schwartz SW goes to the connection but no colors coming out of the connection. The large gauge wire is red. The two small gauge wires are white.
Be careful and ask lots of questions…
Be ever so careful- there are two eyelet red large gauge wires to go to the starter.
One goes from the positive terminal of the starter that is connected directly to the battery and goes to the main relay on top of the pedal box behind the brake booster. That is the main relay for the entire engine harness that feeds the fuel pump cold start Injection system the Computer, the Injectors everything. Let’s call that 3 o’clock.
The other large gauge red wire goes to signal the starter to crank.
Let’s call that 6 o’clock.
If you are uncertain, then get out your ohm meter and test, the two eyelets with the heavy red gauge wires.
The main relay which has a large gauge red wire going into it into the base and you will soon find which one goes to what connection.
That means that the Male spade connector that’s in that plastic sleeve that has the red large gauge wire coming out out of it will be the other eyelet and test between those two points.
One goes from the positive terminal of the starter that is connected directly to the battery and goes to the main relay on top of the pedal box behind the brake booster. That is the main relay for the entire engine harness that feeds the fuel pump cold start Injection system the Computer, the Injectors everything. Let’s call that 3 o’clock.
The other large gauge red wire goes to signal the starter to crank.
Let’s call that 6 o’clock.
If you are uncertain, then get out your ohm meter and test, the two eyelets with the heavy red gauge wires.
The main relay which has a large gauge red wire going into it into the base and you will soon find which one goes to what connection.
That means that the Male spade connector that’s in that plastic sleeve that has the red large gauge wire coming out out of it will be the other eyelet and test between those two points.
And keep in mind in the djet engine Wiring system almost all wires in the engine bay are white.
Fortunately, they all have little tiny tiny numbers printed on them to tell you what they go to. Do yourself a favor and don’t rub too hard with cleaner to read them because you will rub the numbers right off.!
I hope you enjoy your DJ Jet experience!
Fortunately, they all have little tiny tiny numbers printed on them to tell you what they go to. Do yourself a favor and don’t rub too hard with cleaner to read them because you will rub the numbers right off.!
I hope you enjoy your DJ Jet experience!
That’s it!
restart
Well-Known Member
I’m not sure if any thing in these would help:
1977 630 csi electrical troubleshooting manual
And
E12 and e9 blue book wiring diagrams.
I’d you know what you are after I could make a scan of any pages you need.
Re my earlier comment…if removing a tail light wire solves or creates the problem, one might think an errant splice along that wire might be the problem. it looks like you have several locations with modified wiring.
it seems that wire that you mentioned removing in the initial post is a HUGE clue.
Good luck, you have some good help!
1977 630 csi electrical troubleshooting manual
And
E12 and e9 blue book wiring diagrams.
I’d you know what you are after I could make a scan of any pages you need.
Re my earlier comment…if removing a tail light wire solves or creates the problem, one might think an errant splice along that wire might be the problem. it looks like you have several locations with modified wiring.
it seems that wire that you mentioned removing in the initial post is a HUGE clue.
Good luck, you have some good help!
Attachments
I found another loose ground wire group at the ignition coil. I'm assuming the body shop may have covered the original hole that it bolts into. I would like to know where to place a new hole to keep it correct. You guys are awesome with all this helping out a noob.
Attachments
that one probably should be pulled back and accessible for a ground connection under the light access panel. that is probably one of the light grounds or the a/c fan relay ground.
I was just writing the same thing. This attaches to a screw on a panel next to the side marker behind the headlight. You're going to have to pull most of the wiring that you have in the engine bay there back into the headlight area, only have the wires going to the ignition coil protruding through into the engine bay. Depending on your car and whether additional US side lights were added you may have some "extra" wires there.
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David, what @e9Leveque has stated happens on both sides of the car. the one on the drivers side grounds the headlights, relays, turn signal
That isn’t going to reach the turn signal ground. A/C fan relay mounts under the coil and is grounded there, that is one possibility. The second is does this car still have the speed relay box below the coil that triggers the emissions dashpot and vacuum lines on the firewall?
From the zoomed in picture I wasn’t sure what the other wires wrapped in black tape were. In my car the portion reaching the ignition coil is the end of the run, with only a green wire, some red/black and black ground if I recall. I wasn’t sure whether Chris had pulled wiring (including this ground) through the grommet into the engine bay, and if that wrapped portion holds a green (which it looks like it might?) then perhaps it all needed to be pushed through towards the front of the car.
Chris, perhaps you can answer @HB Chris above regarding the other bits that you might have, and also lift off the headlight cover. If you already have a double-brown wire with single connector attached in there then clearly this isn't that one.
Chris, perhaps you can answer @HB Chris above regarding the other bits that you might have, and also lift off the headlight cover. If you already have a double-brown wire with single connector attached in there then clearly this isn't that one.