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The other day I went to the service and changed the front telescopes and the front brake discs together with the brake pads.
At the end of the procedures, they reattached the terminals to the battery and found that the car did not stop honking.
Since I didn't have the patience for the service people to solve the problem, I bought the Lexus repair manual from ebay.
After checking, I found that it is not about the fuse or the steering wheel spiral.
After 2 days of "digging" I discovered that it is the electronic module located next to the fusebox in the engine area.
I've attached some photos to help other members in case they run into this problem.
It was the J/B no.2
I replaced it so all is ok now.
The other day I went to the service and changed the front telescopes and the front brake discs together with the brake pads.
At the end of the procedures, they reattached the terminals to the battery and found that the car did not stop honking.
Since I didn't have the patience for the service people to solve the problem, I bought the Lexus repair manual from ebay.
After checking, I found that it is not about the fuse or the steering wheel spiral.
After 2 days of "digging" I discovered that it is the electronic module located next to the fusebox in the engine area.
I've attached some photos to help other members in case they run into this problem.
It was the J/B no.2
I replaced it so all is ok now.
Awesome job thank you for sharing your fix..
So the Junction Box in the pics had failed?
Yes that was it.
The problem is that no service employee realized the problem.
So I had to go to an electronics engineer who "dug" two days with me to find it.
The title to your post almost made me spit my soda out my nose I was laughing so hard. lol
I never knew there was anything more than a simple circuit board under the relays in the JB no.2 Junction Box going by the electrical drawings- which imply nothing more than simple jumper connections but in your pics it is clear there is quite a bit of logic chips.
And I always wondered why there are heat sink cooling fins located in your pics- can we please see behind circuit board to see behind the cooling fins and what is hiding there???
Here is the detail on that circuit showing the stuff in the J/B for others to see(just horn circuit)- no hint of anything else going on involving logic chips seen so this must've been a nightmare to trace this all out!
Last edited by Margate330; Dec 28, 2020 at 08:16 PM.
The title to your post almost made me spit my soda out my nose I was laughing so hard. lol
I never knew there was anything more than a simple circuit board under the relays in the JB no.2 Junction Box going by the electrical drawings- which imply nothing more than simple jumper connections but in your pics it is clear there is quite a bit of logic chips.
And I always wondered why there are heat sink cooling fins located in your pics- can we please see behind circuit board to see behind the cooling fins and what is hiding there???
Here is the detail on that circuit showing the stuff in the J/B for others to see(just horn circuit)- no hint of anything else going on involving logic chips seen so this must've been a nightmare to trace this all out!
Yes, i will ask the electronic engineer who opened JB no2 to check it , to make me a photo of the other side of the board, just behind the heat sink.
I forgot to ask him at my 1st visit
And yes indeed, was a nightmare to trace those faulty chips.
The other day I went to the service and changed the front telescopes and the front brake discs together with the brake pads.
At the end of the procedures, they reattached the terminals to the battery and found that the car did not stop honking.
Since I didn't have the patience for the service people to solve the problem, I bought the Lexus repair manual from ebay.
After checking, I found that it is not about the fuse or the steering wheel spiral.
After 2 days of "digging" I discovered that it is the electronic module located next to the fusebox in the engine area.
I've attached some photos to help other members in case they run into this problem.
It was the J/B no.2
I replaced it so all is ok now.
anybody can help me to tell where can i buy this chip?
what part number this chip?
i'm doing to fix this module.
thanks 🙏
Has anyone tried to unlock the drivers door with the key while the horn is honking?
you mean the alarm was honking? If so, try locking the car with key and then unlocking. Can’t recall super clearly, I believe that was the trick. Even if it’s locked, lock it “again.”
you mean the alarm was honking? If so, try locking the car with key and then unlocking. Can’t recall super clearly, I believe that was the trick. Even if it’s locked, lock it “again.”
The car does not stop honking (RX400H)
