No tail light license plate or trunk release

Maintenance/Repairs
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1

98 lesabre. I had problems w the starter last winter/fall. I haven’t driven it since march. With winter here soon I got it out. I have no tail light. But also license plate light or trunk release in the car. The release works on the key device. When i first hooked up new starter I put in opposite polarity and blew a fuse for stating it. I found that last winter. I knew the trunk wasn’t opening but just now seen the tail lights. The tail light fuse is good.

I don’t think it b a wire problem. What do I do to determine what’s the problem

2

I do think it is a wire problem. A ground wire problem. A ground wire in the truck that all these lights use.

Check that, and post back.

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I did notice on the wire diagram in book the tail and license lights are both on the same wires. The backup lights do work. If the ground was bad wouldn’t that be on the same ground?

But if it is a ground problem in then couldn’t I tap into the black ground wire and run it to a nut on the top of the trunk?

4

If you have a wiring diagram you should know what is wired to the same ground.

Just go open the trunk and look. Pull the liner back and search for a ground screw with wires. I’d bet there is corrosion or even a broken wire. There is likely more than one ground screw.

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5

Any lighting fixtures on the car’s trunk, wires have to pass from the body to the trunk lid. Every time you open the trunk lid it flexes those wires, and eventually they’ll break. Check the wire harness in the body/trunk lid area. I had to re-wire that section on my Corolla for that same reason. In corolla’s case only lighting on the trunk lid is the license plate light bulb.

This may not resolve the entire problem but seems like a good place to start your investigation.

6

The lights problem is solved. It was a bad power wire.

Now I have to replace a leaking gas tank. I have one from my 91 lesabre that I no longer drive. The tank is like new. The shape is 100% the same. I would put the sending unit from the 98. The only difference is the 98 has some extra electronic connection a foot from sending unit. Not sure what it does. Would it run without that? Is it some sensor? Could it be added?

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That is the fuel tank pressure sensor used for the evaporative emission leak detection system. Without the sensor the check engine light will be on and the computer won’t be able to complete the evap. monitor. You need a fuel tank from an OBDII vehicle.

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I do not want to spend $200 if I do not have too. Is there any way to remove it and replace it into a different tank. Is there something inside the tank that this thing connects too?

Or what if I removed it from that tank and just plugged it in.

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What Happens When the Fuel Tank Pressure Sensor Goes Bad?

There’s some good news and some bad news when it comes to understanding what happens when your fuel tank pressure sensor goes bad. The good news is that it’s possible your car is still going to run fine. In fact, it may not alter the way your vehicle performs at all. However, the problem is that you’re not going to be able to properly pass emissions testing when your sensor isn’t working the way it’s supposed to. And of course, you’re going to have the check engine light on which could definitely be a nuisance. And, if you ignore it because you think it’s just the fuel tank pressure sensor that set it off and something else happens, you won’t know that you have another reason to check your engine.

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I’m going to give it a try. If it runs it runs. It’s not a big job. It’s a winter car.

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If the old sending unit is fine, just replace the tank and use the old pump and sending unit.

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Will do. Might be a couple weeks before I get to it.

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With no way for the powertrain computer to assess the fuel tank pressure, the check engine light will probably be on all the time. That prevents it from being used when there actually is a problem. The most practical work-a-round is for you to check for diagnostic codes frequently. Hopefully if a blinking CEL problem develops, it will still blink the light.

The lack of a way to measure the fuel tank pressure might also prevent the evap system from working properly. The computer opens and closes the vent and purge valves to allow refilling, & cause the fumes to move into the canister, then later into the engine. Could make it hard to fill the tank, or could cause the canister to fill with gasoline and create a odor or safety problem.

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Maybe I read it wrong but I thought the donor car was the one with the sense, not the recipient.

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I believe the donor car is a 1991, the recipient is a 1998. A 91 is OBD I, and wouldn’t usually be equipped w/ a fuel tank pressure sensor.

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Yes switching the yanks. Put the 98 on the 91 since it’s not used. It does not leak at half a tank and the most I would ever put in would b a couple gallons just to start it up.

In a few days hope to get time to put the 91 tank on the 98.

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?? You seem to be contradicting yourself. Explain?

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It is the proper definition of a “swap”.

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Ok. I removed both tanks so far. I installed the bad one from the 98 onto the 91. Since it does not leak on the bottom of the tank. I don’t drive it and would never drive more than a mile away it will be sufficient for that car.

Now all I have left is to install the good tank from the 91 onto the 98. Hopefully I’ll have time over the next few days.

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Do you live in an area with no kind of smog inspections whatsoever . . . ?

Because if you DO live in an area with a smog inspection, you’ll eventually have a fault code and MIL related to the fuel tank pressure sensor and you’re going to have a hard time legitimately getting a certificate

just out of curiosity, why are you hesitant to buy new fuel tank(s) . . . you yourself said they’re onl only $200 or so

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