1973 Custom Cruiser

Thanks. Probably true. I liked my idea of "diving board" better, though.

 

it's like a puzzle. I hate puzzles.

 

Yeah, the second picture. The white casing is browned out at the pink wire (overheated), the orange/black wire is also discolored right above it, and both tie into the relay.

If the body attachment isn't rusty, then you've solved it, from what I can see. At least that's how I'd diagnose it.

Good luck.

 

Yes, the accessory block is a bit discolored, but it still seems to be functional. The pink wire is the ignition coil connection from the relay. As I understand it, when the ignition is on, this wire gets 12 volts and closes the relay, permitting current to flow from the orange/black wire, which presumably comes off the relay, to the white/red wire.

The orange/black wire that's above it and discolored is the power seat wire, and works fine in spite of it's appearance. It looks to be covered with tape, which might have been put on it as a results of whatever caused the melting.

Thanks.

 

curiouser and curiouser

OK, I've done some more checking of the type I should have done earlier.

This relay apparently is NOT for the tailgate motor but is in fact for the rear window. If you look at the wiring diagram (Figure 10-25), the orange/black power lead coming from the accessory block not only connects to the relay, but there is apparently a split which goes straight to the dash window switch. This would suggest that, as long as the accessory block has 12 volts, which it does all the time as long as the battery is connected, the dash window switch will work. But it doesn't work unless the ignition is on. This suggests that the relay is needed, but I don't see this from the wiring diagram. The wiring diagram is confusing here. It shows that the outlet side of the relay, the wire labeled red/white just goes to some kind of harness connector along with a white/blue and tan/white wire, and I don't know where this is or what it connects to. I haven't pulled out the power window switch, and the back of it might very well have these three color wires attached. I'll go look at it now.

The orange/black lead to the relay is always hot, as it should be. When the ignition is on, the pink wire coming from the other side of the accessory block becomes hot and closes the relay. I tested this, and the pink wire does have 12 volts when the ignition is on. If the relay is removed, as it was because I took it to the auto parts store, the rear window will not work. This is correct as the manual says that window operation is controlled by an ignition relay preventing the window from being operated from the dash switch without the key. This means that the relay actually works, and so I probably don't need a new one.

So I still don't know what's going on with getting power to the dash tailgate switch. There is an orange/black power lead connected to it, but it never gets 12 volts no matter whether the key is in or out, ignition is on or not. I'm tempted to take the right side of the dash apart and see where this wire goes. It's apparently not connected at its other end, and I'd like to see why. But I'm worried that I'll take the dash apart and find that this wire just disappears into a harness and reemerges somewhere I can't find.

As I said several posts ago, I can solve this problem by just connecting my own wire from an empty terminal on the accessory block to the back of the dash switch and be done with it. I DID finally connect 12 volts to the other two leads at the dash switch (I used the power lead for the power seats, which, because the carpet and seats are out, is just sitting there unconnected on the floor), and, sure enough, the tailgate motor moves in both directions like a champ. At least THAT much works!

 

Just went and pulled the power window switch out of the dash and looked at the three wires connected to the back, and, sure enough, they're red/white, white/blue, and tan/white. So there must be a connector somewhere between the relay and this switch, as the wiring diagram would suggest, or else these wires just run directly to the switch. Again, I could possibly figure this out if I took the dash apart.

So there must be something similar for the tailgate switch. I did check earlier at the connector under the dash where the gray and purple wires coming from the dash switch connect to the wires of the same color that go to the motor in the rear, and they're fine as I just demonstrated by operating the tailgate motor by applying power to the dash switch terminals.

So where the aich-ee-double-hockey-sticks is the friggin' power lead? Maybe it's just dangling under the dash somewhere waiting to be found and reconnected to something. I haven't looked REALLY closely. It's supposed to have a relay, too, but I don't see that anywhere. It would make sense that it's controlled by the same relay as the one that controls the window, but there's no indication of anything like this in the wiring diagram, which, as I've pointed out, is silent on the issue of the dash-mounted tailgate switch.

Part of me wants to make it correct the way it came from the factory or at least see what's wrong (or at least die trying). The other part of me just wants to make the thing work and be done with it. We'll see which side wins.

Then there's still the issue of why the key switch doesn't operate the tailgate......


In other news, my carpet, which I just ordered yesterday, was shipped today and should be here Thursday the 15th. I want to get all this monkeying around under the dash finished before I put the nice new carpeting in.

 

i said to heck with it and ran new wires to the dash in the 63

good stuff Jaunt

 

I'm about 90% decided to do this. One last thing I want to do first, though, is trace the power wire coming off of the tailgate dash switch. It's got to end somewhere. It SHOULD be connected to power somewhere. If I can find the other end of it, I can hopefully re-hook it to wherever it's supposed to be hooked. Got to take the bottom part of the dashboard apart to be able to see up there. That's for this weekend.

 

looks like the same switch as mine
my radio facia pops off (remove radio knobs, pull gently at tuning and volume holes, working it side to side and out. then the switch comes out the front (will be hard to see from the bottom with the radio in the way)
hope yours is as easy as mine was

 

Removing the switches in a '73 is a piece of cake. The manual says just grab them with your fingers and pull gently, and that's exaclty what you do. Five seconds and they're out. You can pull them forward as far as the wiring attached to the back will allow, and that's easily enough wire to pull the connector off the back.

I see that by the year of your car, the switches were moved to under the radio, and they're mounted behind the dash with only the moveable part of the switch sticking through the dash.

The one downside with my arrangement is that the radio gets in the way of seeing up to the switch from under the dash. I'm hoping against hope that I can see where the wiring goes without having to remove the radio. Removing the lower part of the dash (where the ashtrays are) is easy. If I pull on and wiggle the wiring while looking up under there, I can hopefully see where it goes. As I've said, my fear is that it just disappears into a wiring harness, and I won't be able to see where it comes out the other end. If this turns out to be true, I'll say the hell with it and just run a new, separate wire from one of the unused terminals on the accessory block to the switch. Having the lower dash apart will make this relatively easy.

 

I bet that tailgate is working by EOB today

 

Make it Saturday! At least through the dash switch. Today I'm leaving work a little early and taking the front seat over to an upholstery shop about 40 miles away (nearest one). The wife is coming along, and we're going out to dinner afterwards.

Once I get the dash switch working, I still need to figure out why the rear key switch doesn't move the tailgate (but moves the window just fine). Is it easy to pull the connector off of the key switch, or do I need to remove the key switch to do so?

I noticed on the wiring diagram that the power wire for the tailgate/window is 10-gauge when it leaves the front of the car. It splits at some point along the way according to the wiring diagram, as I've pointed out, and the two wires are 12-gauge, which is what I hadn't noticed before. Ought to be reasonably easy to find where that happens, although pretty much all of the rear-of-car wiring is wrapped in tape, so they're be lots of unwinding that, I assume.

 

I have never had the pleasure of inspecting the key switch area but I would bet this week's pay that David has done it

 

The new carpet arrived today. Very nice. Perhaps a touch redder than the original, but it's going to look great. It was interesting to see just how much the original carpet had faded once I removed it and exposed areas that had been hidden, such as under the sill plates. It's amazing the difference. The carpet was originally a reddish brown, which is what I ordered, and it had faded to a greenish-gray.

Took the front seat and the bottom of the 1/3-size, second seat (the side that folds forward so you can access the third seat) to an upholsterer today, and we found some excellent matches for the color and texture of the original. Should have that back in about two weeks, which means that I now have a hard deadline to get the dang tailgate wiring issue resolved because I want to put the seats back in when I get the front one back. But it ain't going to take two weeks. I'm fixing it one way or the other this weekend!

 

Yaaaaay!

You are now looking at (sort of) a person whose tailgate can now be operated from the dashboard switch, and not because I did any extracurricular wiring, but because the wiring is working the way God and Oldsmobile intended it to!

So what was the problem, you say? The tailgate motor is not working? No. I eliminated that as a possibility weeks ago.

Bad wiring from the back of the car to the front? Well, I had suspected that, but really getting at that wiring required waiting until I had a chance to remove the seats and carpet in anticipation of renewing those. I finally did that last weekend, but my inspection of the wiring revealed no problems.

Closer inspection of the Fisher Body service manual revealed that a relay might be the culprit. I could find only one relay coming immediately off the accessory block, but that one turned out to be for the rear window, and it was working fine.

I was getting close to just running my own 12V power lead from the accessory block to the dash switch, but I wanted to take one last look at the wiring coming from the switch and try to see where the power lead that terminates there terminates on its other end. So off came the lower dash to the right of the steering column. I still couldn't see a whole lot because the radio is in the way, but I could pull on the wiring and see what wiggled under there.

It turns out that the dash switch wiring for both the tailgate and rear window emerge from their wiring harnesses right there in plain view just above the brake pedal, and they terminate at....you guessed it....a relay.

Now THIS relay also has a story. I noticed it some weeks ago when I removed the left lower dash to get at the radio wiring. It was a little odd because, while it looked perfectly fine with the plug connector firmly attached and all wires looking fine, it was held in place by a cable tie wrapped around the lower dash support bracket. It was NOT held in place with any screws. I didn't give this much thought at the time. I figured it was for sure another of the aftermarket wiring jobs I've come across, but, since I didn't know what it did, I didn't connect it in any way with the tailgate or rear window.

Below is a photo of the relay. I apologize for the slight out of focus, but it's difficult to get good close-ups in focus in dark spaces.




There are four wires connected to the relay. One orange/black looking like the wire that goes to the tailgate dash switch, TWO red/white wires, one of which goes to the rear window dash switch and the other I know not where, and the fourth a purple wire that I also didn't know what it did.

I pulled off the connector and checked for continuity between the orange/black lead connected to the relay and the orange/black lead connected to the back of the tailgate dash switch. It was fine. No problem in the wiring from the dash switch to the relay. I checked the two red/white wires for 12 V, and, with the battery hooked up and the key ON, both had 12 V present. The purple wire had nothing.

I figured it as follows. One red/white wire brings power to the relay for the tailgate dash switch, and it should connect to the orange/black wire if the relay is working properly. The other red/white wire provides power to the rear window switch, and the purple wire functions the way the purple wire did in that other relay I was fooling with last week. It's connected to the ignition coil and is energized when the key is on. That closes the relay and allows power to go to the tailgate switch.

So, I figured, THIS relay was the one that was no longer working, and it was off to the auto parts store to order another one.

But wait! I was about 1/3 of the way to the store when I suddenly remembered something. What had to be true for the FIRST relay I was playing with to work? It had to be grounded. What was wrong with the arrangement with the relay I was working with today? By being held in place with a plastic cable tie, it was NOT grounded!

So I hit the emergency Bat-turn switch, out came the parachutes, I stopped immediately, turned the car around on a dime, and went back home to test my theory. (I notified Batmobile Parachute Pick-Up on my way back.)

I reattached the connector plug to the relay, hooked a wire with an alligator clip on each end to the relay housing and a good ground, reattached the battery, turned the ignition on, crossed my fingers harder than I've every crossed them, and pushed the tailgate dash switch.

TA DA! It moved! Both ways! I was so excited, I did cartwheels in the driveway.

So, yes, yet again, an electrical problem in an automobile can ultimately be traced to a bad ground, or, in this case, no ground. I'm sure that the rewiring that was done to this car after its accident resulted in this relay being reconnected but no realization on the part of whoever did the rewiring that it was important that the relay be grounded. So he just hung it out of the way with a cable tie, never realizing the problem he was causing and dooming whoever ultimately tried to fix the problem to weeks of hair pulling.

I still can't control the tailgate from the rear key switch (what do I want, everything?), but that's the next job. At least I solved the front-of-car problem, and at least I can now open and close both the tailgate and the window. What a feeling!