Help Electrical rear seat fuse box issues

[jeffwilson34]

Please forgive this post if it is too long. I will try and enplane what is going on.
The car is not mine, it belongs to an elderly neighbor.
On Halloween night he went to visit his wife in the hospital after she fell and broke her back 2 nights before. The drive is 60 miles.
He said it would not start when he went to leave and had it towed to a shop. They told him the fuel pump went out and charged him $750. The next day they called him to come get it and he made it to the doctor office and it died and would not start back. They sent someone that did something and it ran after that for 2 days. It died at his house and I saw him with the hood up and went to check.. He told me what was going on. I checked the fuse and relay, The relay had a burnt spot on it so I took one out of my Corvette and replaced it to get him going. (my fog light relay is the same) That night he called me saying it was making a funny noise. The fuel pump was running and would not stop. I checked the relay and it was burnt. I did some research and found the rear seat had a problem if rubbing the relays causing issues. I looked at the fuse box good and found it was burned. I told him I would fix it and the next day I found a Chevy dealer 75 miles away with one in stock so I drove and got it and installed it,

Now the car runs good and the relay is not getting hot but the inside lights do not come on when you open the door and right front turn signal stopped working. The bulb is good. I checked all the fuses and even swapped them out from the old fuse box and still no lights. For the heck of it I put the old fuse box back on and the interior lights work and the turn signal works. I double checked everything and carefully put the new fuse box back on and they stopped working again.

Is there something I am missing or did I just get a bad fuse box? Is there anyway to repair it or will I need to buy another one?

I also checked his fuel pump they charged $750 him to replace and it was the original. There was dust and dirt on it. I also love the access hole to replace the pump. Much easier than dropping the tank.

I would love to go confront the shop that charged him to replace the pump but he said to let it go. They did that to him knowing his wife was in the hospital and may never get out, I hope karma catches them soon. How many other people have they did that to?

 

[Happycampers]

Please forgive this post if it is too long. I will try and enplane what is going on.
The car is not mine, it belongs to an elderly neighbor.
On Halloween night he went to visit his wife in the hospital after she fell and broke her back 2 nights before. The drive is 60 miles.
He said it would not start when he went to leave and had it towed to a shop. They told him the fuel pump went out and charged him $750. The next day they called him to come get it and he made it to the doctor office and it died and would not start back. They sent someone that did something and it ran after that for 2 days. It died at his house and I saw him with the hood up and went to check.. He told me what was going on. I checked the fuse and relay, The relay had a burnt spot on it so I took one out of my Corvette and replaced it to get him going. (my fog light relay is the same) That night he called me saying it was making a funny noise. The fuel pump was running and would not stop. I checked the relay and it was burnt. I did some research and found the rear seat had a problem if rubbing the relays causing issues. I looked at the fuse box good and found it was burned. I told him I would fix it and the next day I found a Chevy dealer 75 miles away with one in stock so I drove and got it and installed it,

Now the car runs good and the relay is not getting hot but the inside lights do not come on when you open the door and right front turn signal stopped working. The bulb is good. I checked all the fuses and even swapped them out from the old fuse box and still no lights. For the heck of it I put the old fuse box back on and the interior lights work and the turn signal works. I double checked everything and carefully put the new fuse box back on and they stopped working again.

Is there something I am missing or did I just get a bad fuse box? Is there anyway to repair it or will I need to buy another one?

I also checked his fuel pump they charged $750 him to replace and it was the original. There was dust and dirt on it. I also love the access hole to replace the pump. Much easier than dropping the tank.

I would love to go confront the shop that charged him to replace the pump but he said to let it go. They did that to him knowing his wife was in the hospital and may never get out, I hope karma catches them soon. How many other people have they did that to?

Wow sounds like when this fuse box was shorting out that some wires got fried , wiring insulation was melted off somewhere in the process and these wires could be in a harness under the carpet or wherever it is you should remove the fuses or relays that are continuing to short or blow because what will happen is you will end up with a car on fire , the wires from the fuse box to the items you described as shorting out or blowing fuses need to be checked by a pro and at what repair shop or by whom I have no idea it’s hard to trust someone unless you have been dealing with them for a long time . But a serious issue for the safety of the elderly person and I’m so sad to hear about what happened and how that shop treated the situation . Definitely pull the fuses and relays in question until all of the wires can be checked .

 

[2007LucerneCXL]

The rear seat fuse box is a common problem and GM has a TSB on the repair, it is the fuel pump fuse and relay that short out. The repair may include a new box, new shorter relay, fuel pump fuse and modification to the seat bracket which is what pushed into the box causing the short and possibly killing the fuel pump over time.

There are some changes in the fuse box design over the Lucerne MY, but if it's the same part number and has a matching layout on top and pin out on the bottom there is no reason it shouldn't work. Unfortunately it a repair that is done on a somewhat regular basis and your question/problem hasn't been asked before so it's a assumption that the new box may be defective.

Here's another post on the fuse box relay and the TSB.

2008 Buick Lucerne Fuel Pump Relay

Hi folks, I havent posted in a while but Finally replaced my 2002 Century with a 2008 Lucerne. Ive had this thing for about 2 months. I bought it used with 62k on it. Here is my problem - After driving the car for about 50 miles in the morning I had to make another drive and got in the car...

buickforums.com

 

[jeffwilson34]

The rear seat fuse box is a common problem and GM has a TSB on the repair, it is the fuel pump fuse and relay that short out. The repair may include a new box, new shorter relay, fuel pump fuse and modification to the seat bracket which is what pushed into the box causing the short and possibly killing the fuel pump over time.

There are some changes in the fuse box design over the Lucerne MY, but if it's the same part number and has a matching layout on top and pin out on the bottom there is no reason it shouldn't work. Unfortunately it a repair that is done on a somewhat regular basis and your question/problem hasn't been asked before so it's a assumption that the new box may be defective.

Here's another post on the fuse box relay and the TSB.

2008 Buick Lucerne Fuel Pump Relay

Hi folks, I havent posted in a while but Finally replaced my 2002 Century with a 2008 Lucerne. Ive had this thing for about 2 months. I bought it used with 62k on it. Here is my problem - After driving the car for about 50 miles in the morning I had to make another drive and got in the car...

buickforums.com

I checked all the fuses have power. The box layout is the same but the new one does have extra pins. It came from a GM dealer with all fuses and relays installed. There are extra fuses and relays in the new one that the old one did not have. The diagram in the lid is the same so I am assuming the new one is for a car will all the extra bells and whistles that the original did not come with.

I guess I will go back to the dealer and hope they will warranty exchange it.

 

[2007LucerneCXL]

The original GM Part 20777935 was replaced by 84446208 but should have been a plug and play. Hopefully the dealer will be able to replace the box or see if there is difference.

Buy Genuine GM Auto Parts - Block (Part # 84446208) | GM Parts Store

Discover genuine GM auto parts at GMPartsStore.com your destination for OEM GM parts, like this Block REAR SEAT Part# 84446208 discount prices and fast shipping. Shop now for GM parts

www.gmpartsstore.com

 

[LeperMessiah]

Please forgive this post if it is too long. I will try and enplane what is going on.
The car is not mine, it belongs to an elderly neighbor.
On Halloween night he went to visit his wife in the hospital after she fell and broke her back 2 nights before. The drive is 60 miles.
He said it would not start when he went to leave and had it towed to a shop. They told him the fuel pump went out and charged him $750. The next day they called him to come get it and he made it to the doctor office and it died and would not start back. They sent someone that did something and it ran after that for 2 days. It died at his house and I saw him with the hood up and went to check.. He told me what was going on. I checked the fuse and relay, The relay had a burnt spot on it so I took one out of my Corvette and replaced it to get him going. (my fog light relay is the same) That night he called me saying it was making a funny noise. The fuel pump was running and would not stop. I checked the relay and it was burnt. I did some research and found the rear seat had a problem if rubbing the relays causing issues. I looked at the fuse box good and found it was burned. I told him I would fix it and the next day I found a Chevy dealer 75 miles away with one in stock so I drove and got it and installed it,

Now the car runs good and the relay is not getting hot but the inside lights do not come on when you open the door and right front turn signal stopped working. The bulb is good. I checked all the fuses and even swapped them out from the old fuse box and still no lights. For the heck of it I put the old fuse box back on and the interior lights work and the turn signal works. I double checked everything and carefully put the new fuse box back on and they stopped working again.

Is there something I am missing or did I just get a bad fuse box? Is there anyway to repair it or will I need to buy another one?

I also checked his fuel pump they charged $750 him to replace and it was the original. There was dust and dirt on it. I also love the access hole to replace the pump. Much easier than dropping the tank.

I would love to go confront the shop that charged him to replace the pump but he said to let it go. They did that to him knowing his wife was in the hospital and may never get out, I hope karma catches them soon. How many other people have they did that to?

 

[LeperMessiah]

I hope this problem has been solved.. I bought my car with 56,000 miles on it and around 70 the fuel system failed exactly as yours did. I had it towed to the garage, AAA of course, talk to the shop manager who said sounds like a fuel pump will get you one for 560.. I said great I guess we'll go ahead and do that. Talking to my buddy 2 hours later he said check the fuel pump relay. I stopped and bought a new one on the way back to the shop, put the relay in and drove it home.. eventually replace the fuse box. Now 3 years later I'm having that same exact problem again. I'm going to install external relay to try to solve it.

 

[DanielBrown198241]

I hope this problem has been solved.. I bought my car with 56,000 miles on it and around 70 the fuel system failed exactly as yours did. I had it towed to the garage, AAA of course, talk to the shop manager who said sounds like a fuel pump will get you one for 560.. I said great I guess we'll go ahead and do that. Talking to my buddy 2 hours later he said check the fuel pump relay. I stopped and bought a new one on the way back to the shop, put the relay in and drove it home.. eventually replace the fuse box. Now 3 years later I'm having that same exact problem again. I'm going to install external relay to try to solve it.

If you want to remote mount your fuel pump relay and fuel pump fuse outside of the rear fuse box to prevent further issues, here are the wires and relay pins to wire together.

Pin 85 of your relay goes straight to battery negative terminal.

The Grey factory wire under the rear fuse box in the x1 connector goes to pin 87 on your relay harness.

The Factory green and white wire under the rear fuse box in the x1 connector goes to pin 86 on your relay harness.

The Factory red wire under the rear fuse box in the x1 connector goes to pin 30. Please install an inline fuse holder with a 30 amp fuse between this connection.

That's how I did it and every time I turn my key, my fuel pump turns on and I have fuel.

No need to worry about the seat bracket messing up you rear fuse box or blowing your fuel pump relay any more. This absolutely works cause I just did it tonight.

Here is a link to the fuel pump relay harness I used to do this remote mount job.

https://a.co/d/7oZTNe5

Here is the inline fuse holder I used between between pin 30 and the factory red wire.

Amazon.com

Please use heat shrink wrap to cover these wires but do not use a heat gun due to this being around the rear fuse box and the battery.

After you heat shrink these wires, please use black electrical tape over the connection for further protection.

This worked for me so do this at your own risk.

This is for informational purposes only.

Do not do this if you car is under warranty as this may cancel out your warranty.

I simply supplied this information thinking it may help my fellow lucerne owners.

Thanks for reading and best of luck.

 

[Atmsrus1]

If you want to remote mount your fuel pump relay and fuel pump fuse outside of the rear fuse box to prevent further issues, here are the wires and relay pins to wire together.

Pin 85 of your relay goes straight to battery negative terminal.

The Grey factory wire under the rear fuse box in the x1 connector goes to pin 87 on your relay harness.

The Factory green and white wire under the rear fuse box in the x1 connector goes to pin 86 on your relay harness.

The Factory red wire under the rear fuse box in the x1 connector goes to pin 30. Please install an inline fuse holder with a 30 amp fuse between this connection.

That's how I did it and every time I turn my key, my fuel pump turns on and I have fuel.

No need to worry about the seat bracket messing up you rear fuse box or blowing your fuel pump relay any more. This absolutely works cause I just did it tonight.

Here is a link to the fuel pump relay harness I used to do this remote mount job.

https://a.co/d/7oZTNe5

Here is the inline fuse holder I used between between pin 30 and the factory red wire.

Amazon.com

Please use heat shrink wrap to cover these wires but do not use a heat gun due to this being around the rear fuse box and the battery.

After you heat shrink these wires, please use black electrical tape over the connection for further protection.

This worked for me so do this at your own risk.

This is for informational purposes only.

Do not do this if you car is under warranty as this may cancel out your warranty.

I simply supplied this information thinking it may help my fellow lucerne owners.

Thanks for reading and best of luck.

Bother I know you don’t know me from Joe Blow on the freaking street. But you explaining a bit the external relay for the fuel pump was genius man. I had been fighting this crap for over 2 weeks until I read your post and did exactly as you said. Man since that day I haven’t had anymore issues or at least not those issues. You were definitely a God Send and if you are ever in Central Mississippi hit me you and we go have a cold on me my man. Again brother Thank you tut Thank you.

 

[G-385724]

We purchased our 2011 Buick Lucerne in 2011. We received a single notification letter regarding the fuse box under the rear seat of our 2011 Buick Lucerne January 2019. We never received any additional notifications. The 2019 letter applied to Buick Lucernes up to 10 years of service and 120,000 miles, whichever comes first. When we received the letter 8 of the 10 years were already used and the car had approximately 111,000. I would call this notice a little late. We just had diagnostics done on our Lucerne because it would not start. It turns out that the fuel pump fuse and fuse box under the seat had melted because they came in touch with the seat bracket. A replacement box was installed and it also melted.

Now the Buick dealer is going to provide a smaller box so that it comes no where near the seat bracket. We are looking at a repair cost of over $1,300.00 and the Buick dealer won't stand behind it because the car is 14 years old and has 195,000 miles. The notice should have gone out well before 2019, leaving only 2 years left and very minimal if any miles to address the problem. If the problem was something that occurred after 2019, then the time frame should be 15 to 20 years and the miles closer to 200,000. When the problem on our car finally reared its head, our car has 195,000 miles and is 14 years old. A problem is a problem and responsibility should still go back to the original design.