no power to the purple wire on starter

[TurboDave]

OK, where is this P/N safety switch? Got pictures?

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This is the best I can do, it's crowded up in there. See the white half moon switch on top the column? That's it. The P/N safety switch.

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[RmvBfrFlght]

Sorry, but that isn't the P/N safety switch on our Buicks. That is the backup lights and P/N signal to the ECM switch. Dave, it looks like we were posting at the same time, if you missed it see my post just previous to yours above.

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[TurboDave]

OK, picture of it with the heavy purple wires going to it? No can do because it isn't there. That switch, as I previously posted, it for the back up lights and P/N signal to the ECM.

From the FSM, see note to right of ignition switch:

View attachment 258363
And, where is the P/N safety switch in the above diagram?

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It's right on your diagram above. It's the box near the top incorrectly labeled ignition switch. But that's the device mounted on top the steering column down under the dash that I photo'd.

 

[TurboDave]

It's right on your diagram above. It's the box near the top incorrectly labeled ignition switch. But that's the device mounted on top the steering column down under the dash that I photo'd.

Correction, I'm looking at the wrong part. I can't find the wiring diagram for the switch I photo'd.

 

[TurboDave]

Here's some better pictures of what comes up when I google "87 buick neutral safety switch".

 

[RmvBfrFlght]

The left image you posted showing the switch on the column is mine. I posted that here some time ago. Here are two other pictures I took . This first one is from the passenger side and shows the back up light connector. That is the blue & green wires. Note the open area along with the ORG/BLK and BLK/WHT wires on the lower left (P/N to ECM):

And the wiring diagram for the back up lights, matches the wire colors:

Then a left side view of the column switch showing the P/N input to the ECM. That is the ORG/BLK wire. When grounded the ECM sees that as in P/N, open the ECM sees that as 'in drive.'

The green wire behind it is from the backup light connector. Here it is shown on the ECM wiring, although it states that the BLK/WHT wire is tied to the transmission, it is most likely grounded to the dash someplace:

No purple starter P/N safety interrupt wires anywhere on that column switch. The P/N safety is the mechanical blocker built into the column. Try it, place the shifter in the D position and try to crank the engine. As long as that goofy linkage is adjusted properly the key won't turn far enough to crank the starter.

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[TurboDave]

I stand corrected. So, it's mistakenly called a P/N safety switch.

 

[RmvBfrFlght]

I stand corrected. So, it's mistakenly called a P/N safety switch.

Yes to mistakenly called a P/N safety switch. I discovered this shortly after I got my car. The reverse lights didn't work and the P/N input to the ECM was flaky. It would flicker between P/N and drive when shifter was in the P/N position (grounded).

Cars this old, the grease in the column switch is all dried out. Pull it, open, clean, grease, check the operation, uh, wait a minute... If this doesn't have the two heavy purple wires on it, where the heck is the P/N safety switch? Looked at the shifter, nothing there.

Drove me nuts until one day I was looking at the cranking wiring. Read the note, and went

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P.S. As the reverse lights, there weren't any bulbs in the sockets...