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Discussion Starter #1
My 1993 Cadillac Fleetwood Brougham has no power on the control side of the fuel pump relay pin number 85 i did have power before but i believe this happened when i made a mistake and jump 86 and 85 at the fuse box under the hood after that i found the 10 amp mini fuse for the fuel pump was blown i replaced it with another 10 amp mini fuse.

I don't know where the ECM is located and would like to know it's location and is there a fuse for the ECM located under the hood some where, so i can check the fuse for the ECM or did the ECM go bad? and is it possible i can get a schematic for the fuel pump relay
 

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30 amp #10 & 15 amp #13 underhood fuses are in parallel.
Both power the fuel pump relay and ECM.

Didn't see a 10 amp fuel pump fues on the drawing.
10 amp seems a bit low for the fuel pump.
Wrong fuse or a fuse for something else maybe.

A blown fuel pump fuse normaly means time for a fuel pump & check the in tank connections.

Shorting 85 to 86 at the fuel pump relay is shorting out the ECM fuel pump relay control.
Perhaps the ECM is not damaged because it had short circuit protection in the circuity.
Or it may be smoked.

To power the fuel pump all you need to do is connect 12v+ to the open red lead comming out of the underhood fuse box.

Believe your ECM is in the drivers front corner under the air filter box.
 

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Discussion Starter #3
30 amp #10 & 15 amp #13 underhood fuses are in parallel.
Both power the fuel pump relay and ECM.

Didn't see a 10 amp fuel pump fues on the drawing.
10 amp seems a bit low for the fuel pump.
Wrong fuse or a fuse for something else maybe.

A blown fuel pump fuse normaly means time for a fuel pump & check the in tank connections.

Shorting 85 to 86 at the fuel pump relay is shorting out the ECM fuel pump relay control.
Perhaps the ECM is not damaged because it had short circuit protection in the circuity.
Or it may be smoked.

To power the fuel pump all you need to do is connect 12v+ to the open red lead comming out of the underhood fuse box.

Believe your ECM is in the drivers front corner under the air filter box.
Thanks but I didn't just shove a 10 amp fuse in the fuse box i found my owners manual 10 amp is what the manual say and this is why i like old school cars with classic Differential this is when they used to make Manuals, wow just look at this.

This is a new fuel pump i just change it recently and i'm confuse you say 30 amp are you talking about one of those huge fuse and you say you didn't see 10 amp but after you said 30 amp you say #10 & 15 amp.

I shorted 85 and 86 while the relay was out of the fuse box i had jump a paper clip from 85 to 86 then try to start the car, with out the relay in the fuse box just the paper clip going from 85 to 86.
 

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Your owners manual has a typo in it for the fuel pump fuse.
Look closely at your pic.
Sloppy editing.
I don't care what you pulled out, or found in the misprinted manual.
I'll say it again. 10A for the fuel pump fuse seems low.

You jumped the wrong terminals.
You shorted your ECM.
The fuel pump did not kill the ECM.
Jumping the wrong terminals could damage the ECM.
GM again has a typo in the fuel pump diagram.
85 & 86 are not both grounded.

Power goes thru a larger maxi fuse to a smaller fuse in parallel.
Depending on the year the exact fues value may be different.
Don't have 93 in front of me.
I went off 1995.
1994 has a 40a #4 then goes thru a 15A #13.
 

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Discussion Starter #5
Wow, yeah in fuse slot #16 it's highlighted in yellow with a 20A fuse in the drawing then if you look down at the writings at number 16 it says 10 AMP it was suppose to be 20 AMP, wow how could GM fucked something up so important didn't they look at the manuals before they started selling these Cadillac's so this might be the reason why they only made these Cadillac Fleetwood Brougham from 1993-1996 because they fucked something up so simple and these are nice looking Cadillac's.

#16-Fuel Pump (10 AMP) <<<<<< fuse slot #16
-ENGINE CNTRL.MOD. (ECM)
-FUEL PUMP RELAY
-FUEL PUMP/OIL PRESSURE SW.
 

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"GM f**ked something up so important".
Two different fuse sizes for fuse #16 in the owners manual is nothing more than a minor typo or only partially updated revision before printing.
Very few complaints about these cars to NHTSA.
Some are just customers with unreasonable expectations. Maybe not handled well at the dealership. Complaining about things like wiper blade noise.
Not 1 complaint about a owner trying to fix their own car, not noticing the discrepincy on the owners manual or fues box labeling.
No complaints filed about an owner fixing their 17 year old car shorting the wrong relay socket terminals.

The owners manual is not a service manual.
The rule is vehicle markings superceed everything.
It's labled near the fuse.
Just like many of the automotive micro relays use 1 of 3 standard markings.
1-5
85-87 & 30
Coil, NO, NC, Power / Common
With the diagram printed on most of them.

Fuses don't just burn out.
An experianced GM mechanic would know a 10a fuse is too small for the fuel pump & ECM.

Sorry if you havn't noticed the Fleetwoods / Broughams have been made for a long time.
93 being the last rebody & 94 getting the LT1 engine.
They were discontinued because of market shift.
Same reason why Ford is down to 3 & Dodge only 2 cars for 2020.

Not only the Fleetwoods but all rear wheel drive GM cars were discontinued.
The entire B-body & C-body line, including the Caprice, Impala SS, and Roadmaster, was discontinued, as GM wanted more assembly lines to be able to produce the more profitable SUVs at the Arlington, TX plant. Custom Cruiser was discontinued in 92 due to Olds major restructuring.
Caprices were the most common taxis & police cars.
 

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Discussion Starter #7
I'm checking one more thing before i check the ECM what is this relay on the firewall for it's on the passenger side firewall #30 is the control side of this relay i check the other pins of this relay i got no power to the test light it didn't come on for the other pins but while this relay on firewall was disconnected i pulled the fuel pump relay and i got no power on the dashboard when i turn the key, i plug the relay on the firewall back in and i got power on the dashboard, could this relay be the reason why the ECM is not working?

And do this ECM has a chip that can be transferred to another ECM or is it an all in one ECM?
 

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10 months ago:
I install a new fuel pump in my 1993 Cadillac Fleetwood Brougham before i had change the fuel pump the car was running and it just died like it ran out of gas and i assume the fuel pump went bad because it was cranking but not starting now after changing the fuel pump it still crank but won't start i check the fuel pump fuse with a test light its good i'm not sure about the fuel pump relay because there is fuel in the tank but the new fuel pump doesn't show how many gas i have in the tank when the key is switched on.

And every time the car crank i see fuel leaks on the passenger side under the car from a fuel line i assume its the line with a little black filter i think its a filter, i don't know what it is but its connected to the line that goes all the way up to the carburetor i would like to know what is causing the fuel leaks is it the little black thing connect to the fuel line or some other thing? some help would be appreciated thanks.
So the car was not running right.
OP guesed it was a fuel pump.
Replaced the pump.
Didn't start & leaked fuel when the key was turned on.
So they thought the fuel pump relay may have went bad at the same time the fuel pump was replaced, even though the fuel leaking with the key on was evidence the pump had power.
Wanting to bypass the relay but not using the fuel pump prime lead they got out a paperclip and jumped some terminals till something poped.
Checked the fuses & found a blown 10a fuse.
Unclear if the blown fues was powering the fuel pump, ECM, or something else.
Went to the owners manual out for help.
Couldn't find a section labled "tried to fix my car but now it's worse".
Looked up the fues chart & got turned around by a typo.
Proclaimed GM f**ked up.
Noticed your dash is not working at times. Which may or not be related to unpluging something under the hood.
Asking about replacing the ECM because maybe it got smoked.

At this point there are so many questions a mechanic should ask.
What happened with the fuel leak?
Is the fuel gauge working after the repair?
Then do a basic cranks no start testing with everything conected, including:
Is there is there any and the proper fuel pressure with key on / cranking?
Is there a security / VATS light on?
Does the check engine light come on with the key on?
Is there codes in the ECM?
Is there spark while cranking?
 
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