06 gs300 nothing when pushing start button.

[bebo_vi21]

Good evening, 

Recently bought an 06 gs300. Previous owner stated car doesn't start, crank , nor light up on dash. I recently bought brand new battery for vehicle. And also changed battery on key fob. Still nothing, so I dug into it. I have power to fuses haven't located any blown fuses. I jumped the starter relay and it started to crank so I know motor is not locked. Did a little more digging and decided to open ign. Relay and put a screw driver to make contact and everything lit up like a xmas tree, dash came on heard fuel pump prime. But I dont get anything by me pushing start button. Start button doesn't light up even if I put key fob near it. I have power going to the switch all ignition fuses are good. Jus dont know what else it could be. Maybe reprogramming key?

Thanx in advance for any and all help!!

[RX400h06]

Based on your description, here are a few things to consider:

1. Smart Key System / Immobilizer Issue

If the start button doesn’t light up and the car doesn’t respond to the fob—even when it’s close—it could be a problem with the Smart Key ECU, ID box, or immobilizer system. A common fault code in these cases is B2799, which indicates an immobilizer malfunction. Some users have resolved this by checking for corroded or oxidized connectors, especially behind the driver-side kick panel.

2. Key Fob Reprogramming

Yes, reprogramming the key fob might help—especially if the car isn’t recognizing it. You can try a DIY method using a programmer like the Dorman 99389 kit, or follow a manual sequence:

• Press the start button without the brake to enter accessory mode.
• Hold the lock button on the fob for 10 seconds.
• Turn off and remove the key/fob.
• Try locking/unlocking with the fob again.

3. Brake Switch or Neutral Safety Switch

If the brake switch isn’t sending a signal, the car won’t allow a start. Same goes for the neutral safety switch—try starting in neutral instead of park, just in case.

4. Fuel Pressure Sensor

This sensor has been known to cause no-start issues on the GS300. It’s buried under the intake manifold, but replacing it has solved similar problems for others.

5. Grounds and Connectors

Double-check all grounds and connectors, especially those related to the ignition system and ECU. A loose or corroded ground can cause all sorts of ghost issues. Good luck!

[bebo_vi21]

I tried starting in neutral and nothing did try with and without brakes nothing. U said driver side kick panel exactly where so I can go check that out. Turn off an remove fob meaning release switch and move fob away from vehicle? I disconnected the pressure sensor as I read on another post and still nothing. Located and double checked grounds they all look good and connected. I was thinking to jump solenoid again n see if I can get a code on my scanner see if that gives me anything. Thanx

[RX400h06]

How do you know that the fuel pressure sensor is good? Do your brake lights work? I don't think I mentioned the driver's side kick panel.

[bebo_vi21]

Every video or article ive read most suggest to unplug it and if it starts that would be the issue. I could plug it back in and try again. And yes you mentioned driver side kick panel under the 1st section for the smart key of your first post. 

[bebo_vi21]

And yes my brake lights work and flashers nothing else mo headlights no horn nothing!

[bebo_vi21]

Just scanned vehicle got the B2799 code. Only code showed up on scan tool.

[dcfish]

B2799 –Toyota: “Engine Immobilizer System Malfunction”

OBD II fault code B2799 is a manufacturer specific code that is defined by carmaker Toyota as “Engine Immobilizer System Malfunction”, and is set when the PCM (Powertrain Control Module) detects either a communication error between itself and the transponder key, or a malfunction in one or more communication lines between itself, the transponder key, and the immobilizer control module. Note that this code can also be set when one or more implicated control modules detect incorrect security codes being transmitted from the key to the PCM or immobilizer control module.

Modern automotive security/anti-theft systems are highly complex systems that depend on the transmission and receipt of extensive strings of security codes, and in practice, the key, immobilizer control module, and the PCM all contain the same codes in the same configuration. Note also that on some Toyota applications, the same codes are programmed into the central locking system, meaning that only the correct key can lock/unlock the vehicle remotely using the key fob.

In terms of operating principles, the immobilizer control module is connected to a receiver that fits around the ignition lock, and when the key is inserted into the ignition lock, the receiver “reads” the security information that is programmed into a chip in the key. This information is amplified to increase accuracy, and then relayed to the immobilizer control module, which compares its own programming with that received from the key. Only if all the transmitted and received security codes match, will the immobilizer enable the fuel and ignition systems to allow the engine to start.

While the above description is admittedly a gross over simplification of an extremely complex system of checks and verifications, it will nevertheless suffice to illustrate the point that unless all the pre-programmed security codes and other vehicle identifying information contained in the key, PCM, and immobilizer control module match exactly, the immobilizer will not allow the engine to start. In some cases though, the engine may start but will be shut down by the immobilizer after about two seconds.

[bebo_vi21]

Car jus stopped randomly. It's weird took the key to locksmith says key is all good. car is a push to start. Is there a hidden spot to put the actual key in to turn? I'm lost Car is parked in a bad spot trying everything I can think of to get it going and out of the way. Key was checked good, push button. All checked out good all fuses good, big fuse near battery near brand new. I can jump the ign. relay and everything lights up. I also jumped the starter and she turned over and rumbled a bit. It's jus not doing it on its own!!