ECM wiring diagram

FRAGO

MEMBER
1991 BUICK PARK AVENUE
3.8L
V6
2WD
AUTOMATIC
160,000 MILES

I'm looking for a wiring diagram of the three connectors related to the ECM. The former owner of my car has made some modifications on the pink and black lead and I would like to know what he has done?
Thanks for helping.
Franck

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Monday, September 28th, 2020 AT 1:20 AM

13 Replies

ASEMASTER6371

MECHANIC
52,797 POSTS

Good morning,

I attached the wiring diagram of the ECM as you requested.

Let me know if you need any other help.

Roy

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Monday, September 28th, 2020 AT 1:47 AM

FRAGO

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Yes, I said thanks and said that I will investigate and give you feedback.

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Monday, September 28th, 2020 AT 2:06 AM

ASEMASTER6371

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You are welcome.

Always glad to help.

Roy

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Monday, September 28th, 2020 AT 2:12 AM

FRAGO

MEMBER
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Yes, I did but same problem again with the message system. So I did investigations but the wiring diagram does not match with my ECM. The faulty pink and black is number a2 on the black 24 pins connector. What did you think about that?
Franck

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Monday, September 28th, 2020 AT 11:28 AM

FRAGO

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See the attachment.

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Monday, September 28th, 2020 AT 11:30 AM

ASEMASTER6371

MECHANIC
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Okay, in the diagrams I sent the pink/black is a power feed to the ECM.

Is that what this wires does?

Roy

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Monday, September 28th, 2020 AT 12:26 PM

FRAGO

MEMBER
32 POSTS

Hi Roy.

I assume that what is important is the pin number and not the color, right? The diagram leads color does not match with my connector. On my ECM, the connectors are black and green not orange.
I have to do more investigations to really conclude about the function of this pink and black lead.
Have a good day.
Franck

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Monday, September 28th, 2020 AT 11:53 PM

ASEMASTER6371

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Can I have the VIN number from the car please?

Roy

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Tuesday, September 29th, 2020 AT 1:04 AM

FRAGO

MEMBER
32 POSTS

Hi Roy,

VIN is: 1G4CW53LOM1702281.
I did more investigations and found out that the wiring of my car corresponds to a model 1993!
Maybe because it was sold in Europe (I'm French).
In this case the pink and black lead must be from/to the MAF?
What do you think about that?
The strangest thing is that the red replacement lead goes to a harness like if it was from the manufacture.
Is it a spare lead in case of?

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Tuesday, September 29th, 2020 AT 9:19 AM

ASEMASTER6371

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The VIN comes back the car I gave you for the diagrams.

What does not function that makes you want to replace this?

Where is the other end of the wire?

Roy

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Tuesday, September 29th, 2020 AT 12:39 PM

FRAGO

MEMBER
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Hi Roy,

I bought this car that has not run for a while. I had to remove the dashboard to fix the HVAC and I discovered that tricky modified pink and black lead. Somebody has cut and strapped it with a red lead that goes I don't know where yet. Before putting back the dashboard, I just wanted to be sure about the purpose of this red lead.
I think that I have everything to finish this investigation. I will give you feedback if you want.
Thanks again for helping, I really appreciate your patience.
Merci et bonne journée,
Franck

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Wednesday, September 30th, 2020 AT 12:54 AM

ASEMASTER6371