Electrical problem electric roof and seats Cadillac ElDorado 1975

[Alf Skywalker]

Hello again friends.
I open this new thread after solving the previous problem with the ignition cylinder, for which I am very grateful to this forum and to the wonderful users who have helped us. Thanks from my heart.

The problem that has arisen now is that when activating the switches of the hood or those of the seats they do not work. The fuses in the box under the steering wheel are all good (I don't know if there are more fuses elsewhere).
By activating any of these switches it can be seen that there is energy consumption because the lights of the panel change in intensity.
We have checked and cleaned all the connections and we don't see anything.
Please, any support? What cable could it be that is disconnected? Could it be an electrical relay?
Thanks so much, I wait for your answer.

[TJ Hopland]

The hood (where the engine is) is just a mechanical cable, are you talking about the trunk release?  If we are talking about the trunk do you hear anything if you listen close near the key area while someone else pushes the button?   

Seats if you are seeing lights dim but you don't hear anything I would guess that the mechanisms are just stuck with old grease and or the drive cables have broken or detached and the mechanism is just wedged at an angle and stuck.    There is a single motor for each seat that drives a transmission.   Instead of different speeds this transmission has different outputs that are electrically activated.   

You press forward a solenoid engages the forward gear at the same time the motor starts turning and that output spins 2 drive cables, one going to each track.   If one of those cables isn't doing its job maybe because some object under the seat knocked it off what could have happened is someone tried to adjust the seat but only one side moved and they kept pressing the button till the mechanism was at such an angle that it just jammed up and now the motor doesn't have enough power to un jam it.     The grease also gets hard and sticky with age.

[Alf Skywalker]

Hi TJ Hopland.
First of all thank you for your quick response; secondly to apologize for not exposing my problem correctly (my bad English). The problem is with the electric roof top.
What you tell me about the seats we have already done: grease them and move them at the same time as the switch is activated, but they do not move.
I think it is a cable, fuse or relay, which we have disconnected without realizing it, because before disassembling the entire steering column (which is all full of hundreds of cables in this area ...)  to carry out the previous repair, everything worked perfectly.

[TJ Hopland]

If you can see lights dim its not a fuse issue.     Both the seats and the top use a cable driven geared mechanism and the same somewhat unusual relay control system with the same model of relay.   

If there is a cable issue the motor can be turning but its not able to actually turn the gears at the other end.   

If there is a problem with the relay partial power still gets sent to the motor but it doesn't have enough power to actually do any work.   The motor can actually be damaged by a bad relay because of this odd partial power from the switch and partial from the relay design.   

[Matti R]

Buenos Dias Alf,
Have you checked these:
- is there 12v voltage in orange wire under the seat? That brings the power to the seat motor.   If there is 12v, then the problem is in the switch or motor or stuck cables.
- have you tried the switches when motor is running? It will give a bit more power to motors.

[Alf Skywalker]

Good Morning.
I have tried all your advice, I have cleaned all the possible connections, I have checked to see if there were loose cables, I have greased all the parts well, I have verified that power does arrive, but the roof and the two seats still do not work. As a curious fact to tell you that the light that warns of "open hood" has stayed on.
I am almost convinced that we have connected something wrong, or that there is a missing cable to connect, because it is a great coincidence that the two seats and the electric roof have broken down at the same time.
Tomorrow I'll ask the mechanic to try to check these two things for power.

By the way, this is the best data sheet I have found to review the entire installation tomorrow. Do you know if there is any other more detailed one? Thanks!

[Cadman-iac]

Hi Alf,

  Let me ask you this,  does your car have any rust on the floors?

And have you tried using a temporary grounding strap or wire to the seat frame to see if that makes any difference?
Because if you're getting power to the seat and the top motor, then to complete the circuit, after the power goes through the switch and then to the motor, it must go to ground.

I'm checking my books for a schematic for the seats and the top for you.
I found these for the seats, but you will have to pick the one that you have. There's a couple different options.


  The last picture is of the only schematic I could find on the convertible top, so I hope it gives you what you need. Unfortunately it doesn't show the front end of the top harness or the top switch, just the wiring between the switch and the motor.
But this circuit is fairly simple. Power from the fuse box to the switch, then from the switch to the relay at the motor, then to the motor itself.
What I can't tell is if the top motor has 2 separate windings, one for each direction, or if it just has one winding and the switch reverses polarity to make it run in one direction or the other.
I was not able to find a complete wiring schematic for this, so there's no way to tell. What I did find is really of not much use, but maybe you can find something in it that helps.
  Good luck with your repair.

Rick

[Alf Skywalker]

Thank you.
It is a pleasure to have people like you. You have resources and solutions for everything.
Already solved. For some strange reason the orange wire was not getting enough current. The solution has been simple, put a direct current cable to the seat, and with this the two seats and the electric hood already work. Mysteries of life ... Thank you again friends !!

[bcroe]

. For some strange reason the orange wire was not getting enough current. The solution has been simple, put a direct current cable to the seat, and with this the two seats and the electric hood already work.

That sounds like, somewhere in that orange wire run, is an
oxidized connection that limits current.  When I find these
(way too often on aged cars), I solder the wires together
without a connector.  Bruce Roe

[Alf Skywalker]

Well, it has gone bad again. The mechanic put direct electric current on it and everything has been working fine until this morning. This morning when checking the controls of the seats they have returned to stay if the two seats and the electric roof work. And now when you try to put a direct electric current into it again, a fuse is blown. The mechanic says it has to be a relay, but he says that with the mess of cables and relays under the steering wheel, he doesn't know where to start looking. Do you know what relay or what piece may be the one that is causing the problem?
I'm desperate... 

[Cadman-iac]

Alf,
The relay for the top is located in the rear behind the back seat, right beside the top motor.
The relay, or relays if you have a split seat, are normally under the seat next to the motor.
  I just pulled the wiring out of my 72 eldo convertible, and I noticed that the power lead goes from the bulk connector under the dash on the left side and just above the emergency brake assembly.
That wire goes down to the floor and along the inside of the rocker to the rear of the passenger compartment. About 3/4's of the way back, it's spliced to another wire of the same color and size that then goes both directions, one to the seats, the other one to the top motor relay.
It should be a 10 or 12 gauge orange wire with a black stripe on it.
Probably what happened is that splice has corroded and caused your lack of power.
Hope this helps.

Rick

[Alf Skywalker]

Thank you, Cadman-iac!!
Tomorrow I will pass your information on to the mechanic who will surely facilitate the work between so much cable and relay !!!

Alf,
The relay for the top is located in the rear behind the back seat, right beside the top motor.
The relay, or relays if you have a split seat, are normally under the seat next to the motor.
  I just pulled the wiring out of my 72 eldo convertible, and I noticed that the power lead goes from the bulk connector under the dash on the left side and just above the emergency brake assembly.
That wire goes down to the floor and along the inside of the rocker to the rear of the passenger compartment. About 3/4's of the way back, it's spliced to another wire of the same color and size that then goes both directions, one to the seats, the other one to the top motor relay.
It should be a 10 or 12 gauge orange wire with a black stripe on it.
Probably what happened is that splice has corroded and caused your lack of power.
Hope this helps.

Rick

[Cadman-iac]

No problem,  and good luck with it. I hope it's just that simple.
The only problem is that to get to the wiring, you will need to remove the kick panel behind the emergency brake, and you will have to take up the sill plate, and the carpet front and rear along the rocker. The seat may be in the way too,  so be prepared to take it loose as well.
That bulk connector under the dash is about 4 inches long, and here's a picture of what you're looking for. This is where the power starts from on its way to the seats and top. The red pieces are the connectors that will be plugged into it.
And the feed wire for this is connected at the top by a crimp connection. All of the options that receive power with the key off are supplied by this block. The cigarette lighters,  the courtesy lights, seats, top, etc.

Rick

[Alf Skywalker]

Great Rick !!!
I think that with all this the problem for the mechanic is greatly reduced. It is a tremendous luck to have me and this forum helping people like you so effectively and in a selfless and gratuitous way. Thank you very very much.

No problem,  and good luck with it. I hope it's just that simple.
The only problem is that to get to the wiring, you will need to remove the kick panel behind the emergency brake, and you will have to take up the sill plate, and the carpet front and rear along the rocker. The seat may be in the way too,  so be prepared to take it loose as well.
That bulk connector under the dash is about 4 inches long, and here's a picture of what you're looking for. This is where the power starts from on its way to the seats and top. The red pieces are the connectors that will be plugged into it.
And the feed wire for this is connected at the top by a crimp connection. All of the options that receive power with the key off are supplied by this block. The cigarette lighters,  the courtesy lights, seats, top, etc.

Rick