Jump to content


Ls400 How To Fix The %$^# Cigarette Lighter!


914lps

Recommended Posts

If you have had your front cigarette lighter stop working, and have done a search of this forum, you know no one has found a fix past checking and replacing the 15 amp fuse located under the drivers side panel.

Well my front lighter went dead when a shop was working on the center console. They ended up telling me it was an issue with the wiring harness.

Well the easy thing would have been to give up and run a new power source and plug. But I wanted to fix it.

I replaced the 15 amp fuse. That got the rear lighter to work, but the front one was still dead.

I pulled the complete ashtray out of the car ( directions on LexLs site).

Using a volt meter and Ohm meter I started to trace and check all wires. I fount I had power at the connector from the harness to the ashtray assembly. I even had power down to the connector on the lighter [plug itself wire the +12volts connect to the lighter). Ground was also good. But the plug was still dead!

Well this made no sense to me. So I took the lighter socket plug apart. I cleaned all surfaces etc. But still no power when plugging into the socket. I had power on the back side connectors, but not on the inside of the plug!

I then started looking at the connectors on the back again. Well you have 3 connectors connecting the +12 volts to the lighter. Four if you count the ground wire.

The connector that connects the ashtray to the wiring harness has 4 wires on it. 2 are yellow. They go to the lights on the ashtray. One is black. That is the ground wire. Then you have a gray wire. That Gary wire feeds the 12+ volts to the lighter! If you look at it you will see it is a thin wire and I did not feel it was right for a 15 amp circuit.

Well follow that +12 volts to the lighter. That connects to a crimp fitting and it looks like that feeds the power to the plug. Surprise! It does not, it is part of another connector built into the plug. This connector is a piece of brass. Right across from where that wire connects, you will see a short black wire that connects to two brass crimp points. That is a fusible link!!!!!!!! I had to look at mine with a magnifying glass to see that it blew!. This black wire is crimped to the brass pieces that the +12 volts is crimped to. That short black wire is then crimped to another brass crimp point. It is this point the really connects to the center power point of the lighter!.

I used a small knife to open up the crimps and pulled the black wire out. I replaced it with a new wire and re-crimped both connection points. Bingo power was back to the front lighter.

If you carefully take the lighter apart by undoing the nut on the back and very carefully inspect the parts you will see the insulating washer the separates the +12 volts from the real connection point though the little black wire.

I'm guessing Lexus felt that the thin gray wire they used was to light for a 15 amp draw, so they fused the lighter with a link!

So you can fix it my way or try finding a new lighter to install

I give Lexus a big :chairshot: For this one!

It only took me 4 hours to figure out what the deal was on this.

Link to comment
Share on other sites


Strange but probably intentional by Lexus. The fusible link is probably the fuse of last resort for this circuit. Since it is easy for a coin to fall into the outlet and create a dead short it deserves secondary protection.

Here's the scenario.

..."Coin or metal gum wrapper gets into outlet creating short. Lighter now sitting on top of it so coin not noticed. User changes fuse in fuse panel and it instantly fails again. Perplexed user trys another and same thing. Frustrated user now puts a bigger fuse in circuit. Now wire can overheat or worse. So Lexus put a failsafe wire link just to protect wire harness from melting or catching fire."...

Link to comment
Share on other sites

  • 6 months later...

I just fixed a similar problem on my '91. Everything the OP said was right for my car too. But in my case the fusible link was still OK. The problem was an open circuit between the fusible link wire and the brass bracket. Once I isolated this as the problem, using the OP's guidance and a continuity checker, I just had to gently crimp the bracket to refresh the contact with the fusible link. That did it for me.

Link to comment
Share on other sites

If you have had your front cigarette lighter stop working, and have done a search of this forum, you know no one has found a fix past checking and replacing the 15 amp fuse located under the drivers side panel.

Well my front lighter went dead when a shop was working on the center console. They ended up telling me it was an issue with the wiring harness.

Well the easy thing would have been to give up and run a new power source and plug. But I wanted to fix it.

I replaced the 15 amp fuse. That got the rear lighter to work, but the front one was still dead.

I pulled the complete ashtray out of the car ( directions on LexLs site).

Using a volt meter and Ohm meter I started to trace and check all wires. I fount I had power at the connector from the harness to the ashtray assembly. I even had power down to the connector on the lighter [plug itself wire the +12volts connect to the lighter). Ground was also good. But the plug was still dead!

Well this made no sense to me. So I took the lighter socket plug apart. I cleaned all surfaces etc. But still no power when plugging into the socket. I had power on the back side connectors, but not on the inside of the plug!

I then started looking at the connectors on the back again. Well you have 3 connectors connecting the +12 volts to the lighter. Four if you count the ground wire.

The connector that connects the ashtray to the wiring harness has 4 wires on it. 2 are yellow. They go to the lights on the ashtray. One is black. That is the ground wire. Then you have a gray wire. That Gary wire feeds the 12+ volts to the lighter! If you look at it you will see it is a thin wire and I did not feel it was right for a 15 amp circuit.

Well follow that +12 volts to the lighter. That connects to a crimp fitting and it looks like that feeds the power to the plug. Surprise! It does not, it is part of another connector built into the plug. This connector is a piece of brass. Right across from where that wire connects, you will see a short black wire that connects to two brass crimp points. That is a fusible link!!!!!!!! I had to look at mine with a magnifying glass to see that it blew!. This black wire is crimped to the brass pieces that the +12 volts is crimped to. That short black wire is then crimped to another brass crimp point. It is this point the really connects to the center power point of the lighter!.

I used a small knife to open up the crimps and pulled the black wire out. I replaced it with a new wire and re-crimped both connection points. Bingo power was back to the front lighter.

If you carefully take the lighter apart by undoing the nut on the back and very carefully inspect the parts you will see the insulating washer the separates the +12 volts from the real connection point though the little black wire.

I'm guessing Lexus felt that the thin gray wire they used was to light for a 15 amp draw, so they fused the lighter with a link!

So you can fix it my way or try finding a new lighter to install

I give Lexus a big :chairshot: For this one!

It only took me 4 hours to figure out what the deal was on this.

Oops, sorry, but after reading this post you might want to go back and replace that "fusible" link.

ALL automotive cigarette lighters have this same "fusible link", not to limit current flow but to prevent the cigarette lighter itself from starting a FIRE. That fusiable link is in reality a soft lead wire link that will melt open if the heat of the lighter lasts to long or gets to HOT.

I used a small link of lead solder to replace mine.

Link to comment
Share on other sites

  • 1 month later...

I had a similar problem with my front lighter not working on my 1995 celsior and i just sprayed terminal cleaner on the connector for the lighter and on the rear of the lighter itself to get 12 volts on the inside of the lighter. My lighter still didn't work thou, there was 12volts present but the lighter wasn't staying down when i pressed it in. if you look inside the lighter there are two tabs on either side, just get a small screw driver and pry them out and it worked fine. Just a bit of info incase someone needed it.

Todd

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.



×
×
  • Create New...

Forums


News


Membership