Rear power window questions

Laldog

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I have a few general questions regarding my rear power windows.
They have no apparent power coming to the leads.
Windows operate from an independent power source (jump pack) but will not operate from front switch or rear armrest switch.

1. Since both front windows are operating fine (ok, slow but functioning), does this mean that the window relays can be eliminated as the potential source of the rear window problem?

2. How do the red button circuit breakers orientate? Are they right to left or front to back? (In other words does the left-side button control the front and back windows on the left side, and the right side button control the front and back right-side windows) or does on button do both front windows and the other do both back windows?

3. Does the rear armrest mounted switch have to be wired in for complete functioning, or does the front console switch operate independently of the rear?

4. The Prosperos wiring diagram (photo) seems to display a central point where a number of red wires converge. Where is this convergence or am I exposing my inability to read simple wiring diagrams?

Is there a treatise or doctoral thesis available somewhere that explains how the power window system functions? I'm really losing it....

Thanks in advance.
 

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HB Chris

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The Prosperos diagram doesn’t show later switches and circuit breakers, you need the Blue Book 74 diagram. It is in our FAQ. I don’t know if left or right but if one switch is unplugged such as the rear then other switch will not operate so all need to be plugged in.
 

Ohmess

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The convergence you see on the wiring diagram is a chassis ground. The wires are brown. These wires need not be grounded to the same point on the chassis, but that is how the car was manufactured.

If I am reading the wiring diagram correctly, one circuit breaker is for the front and the other is for the rear. For the rears, the power wire from the breaker is green/blue to both of the switches. And on both of the switches, it is connected to terminal 4 on the switch. You have a connector, whereas my car has individual wires, but in either case I believe there are numbers on the switch that correspond to the connections in the wiring diagram (and perhaps there are numbers on the switch connectors as well, I just don't know).
In any event, you should be able to pull one of your rear window switch connectors, identify which connector goes to terminal 4 either by looking at the connector or the switch (or both), and test whether that wire has power with the ignition switch on. If not, you need to go upstream to the circuit breaker and check to see if it is tripped. If not, see if that has power.
 

HB Chris

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He has a plug with no spades and only two wires to each motor, much simpler than early switches.
 
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Laldog

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The convergence you see on the wiring diagram is a chassis ground. The wires are brown. These wires need not be grounded to the same point on the chassis, but that is how the car was manufactured.

If I am reading the wiring diagram correctly, one circuit breaker is for the front and the other is for the rear. For the rears, the power wire from the breaker is green/blue to both of the switches. And on both of the switches, it is connected to terminal 4 on the switch. You have a connector, whereas my car has individual wires, but in either case I believe there are numbers on the switch that correspond to the connections in the wiring diagram (and perhaps there are numbers on the switch connectors as well, I just don't know).
In any event, you should be able to pull one of your rear window switch connectors, identify which connector goes to terminal 4 either by looking at the connector or the switch (or both), and test whether that wire has power with the ignition switch on. If not, you need to go upstream to the circuit breaker and check to see if it is tripped. If not, see if that has power.
Thanks for this. It clears up alot my questions.

Still stuck though.
First I reconnected ALL 4 window switches and confirmed correct wire orientation

Second I checked for power at terminal 4 on all switches: nothing there. No power

Next, I checked connections at circuit breaker and confirmed that circuit breaker was NOT tripped. It was receiving power however.

So now I'm further stumped.

Could it be a ground wire issue? Where is the chassis ground located?. I don't really want to pull up my carpets and insulation, but its looking like I might have to

The interior is in shambles anyway, so what's one more thing??

Anyway, thank you all for your help.
 

Laldog

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Ok. Here's what I know:

It doesn't appear to be the switches. 2 good ones switched around yielded no positive results.
Power comes out of both circuit breakers, but power does NOT make it down to the console switches for the rear windows.

SO, I'm thinking there is some kind of break in the line between the circuit breaker and the console switches for the back windows.

May be a overly simplistic and entirely optimistic, but lets see what happens when I unroll that 5 lb. ball of tape under the shifter knob.
I'm going in. Wish me luck.
 

bavbob

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How do you know the two are good? Did you then put the two in series for a single back window and see what your result was? Are you checking for current or voltage?
 

Laldog

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How do you know the two are good? Did you then put the two in series for a single back window and see what your result was? Are you checking for current or voltage?
Thanks Bob.

I know the 2 switches are good because they both worked on the 2 front windows.

I did check for current on all four switches, but I'm going to try a continuity check or similar tomorrow.

I didn't even THINK of putting them in series. Great idea.
 

steve in reno

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Just a btw statement.
I have an early 2800 cs and my rear armrest switches are and have been for a long time, deleted.
Function of front switches is normal.
 

Laldog

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Just a btw statement.
I have an early 2800 cs and my rear armrest switches are and have been for a long time, deleted.
Function of front switches is normal.
Thank you Steve.

I have just about zero chance of anyone sitting in the back seat, so the rear switch delete would be a no-brainer.

Does anyone else have experience with the armrest switch delete. That would solve my problem by half.

Thanks in advance.
 

Laldog

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What the ....

Ok so I found a serious break in the wires (it looks they were definitely cut), but as my luck would have it, the wires don't match up!

One side of the cut has three wires, while the other has 2. One of the wires is energized, while the other is not.

I remember when I bought the car (15 years or so ago), the rear windows were sealed shut with silicon caulk, but I didn't think the wires were cut too.

I give up.
 

Laldog

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Also, what's up with these clips?

They're not OEM are they?
 

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tferrer

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Ahh, the splendor, dare I say the unmitigated bliss of the E9s wire harness! The design and engineering is the 8th wonder and the pleasurable hours you will spend gazing upon it in sheer wonder and awe!
 

steve in reno

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I just removed switches and left wiring in place. No jumpers.
When I reupholstered the arm rests I never cut out the switch hole.
And you will have 2 extra switches.
It may not work for all years.
 

HB Chris

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On late 73 and all 74 if you remove rear switch the switch on the console for that window will not work. I just tested this again right now. You need two known good switches to test each side for the rear windows.
 

HB Chris

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The left rear switch has five wires: terminal 1- blue, 2- black, on the other side 3- blue/red, 4- green/blue, 5- black/red. Wires 3 and 5 come from the console switch, 1 and 2 go to the motor, this why rear switch must be in place and working. The terminal are numbered on the switch or plug. You can only use the 74 wiring diagram as it has the two wire motors.
 
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