2005 Lexus LS400 - Page 4 - Answered Questions & Fixed issues

Depending what part of the country this car was purchased originally, the alarm system can be different. These are after market systems installed by the distributor or dealership. Different systems are connected differently. Either way the alarm system is connected to the engine controller and or the main electrical circuit. This has to be removed and the circuit reconnected. I would advise taking to a car alarm specialist and have them replace or remove it.

Lexus LS 400... | Answered on Feb 12, 2014 | 533 views

-Mostly coil.

Good luck


Lexus LS 400... | Answered on Jan 11, 2014 | 86 views

You have a short circuit or a bad switch somewhere near the fuse box or behind the fuse box as Ecu is also been not getting the complete voltage so kindly check the short circuit while testing from the battery wire to fusebox .Do it early before it blows your ecu.

Lexus LS 400... | Answered on Dec 12, 2013 | 66 views

Yes near the passenger side of the car close to the floor is the actuator, it is about 6 inches away from your blower motor closer to the center of the car, there are three screws holding it in and one is very difficult. Once you pull it out you can turn the door by hand, just have the heat blowing when you do it so you know when you have it on heat. after you have done this to get heat fixed for now watch your actuator as you turn it from cold to heat and back again, "if it turns then your blender door is the issue. if it doesn't then check the voltage going to it, if you do not have any pull the switch out and check for voltage there. If your actuator doesn't move and you have voltage, the actuator is the issue. If you have no voltage at the actuator and you have voltage to the switch it is the switch that is broken. hope this helps you.

I’m happy to assist further over the phone at https://www.6ya.com/expert/brock_d67526d2a834c47e

Lexus LS 400... | Answered on Dec 11, 2013 | 123 views

Okay, I am not convinced it is the spark. But there is a chance. The fact that torching the plugs allowed it to start tells me you engine is flooding. Do you smell gas? If you open the throttle body with the air cleaner off, does vapor come out when the engine had recently cranked? If it is electrical, then power to both ignition modules is failing, which means A. the ECM is not providing power to the modules, or B. The engine crank sensor has failed. The Cause could be a bad connection to the ECM.
A scope will indicate whether or not the proper pulses are being input and output from the ECM to the modules. Of course it will need to be tested when it is not working compared to when it is. When cranking, the tach should move indicating rotation of the crank, if not, there is a good chance the crank sensor is no good.

Lexus LS 400... | Answered on Nov 16, 2013 | 247 views

Have the cold start fuel inkector checked for flow.

Lexus LS 400... | Answered on Nov 16, 2013 | 285 views

I'd have to guess that one of the door switches has failed. Check one by one and replace the bad one.

Lexus LS 400... | Answered on Sep 30, 2013 | 181 views

Need to know what year and what engine size you have in order to help....

Lexus LS 400... | Answered on Sep 21, 2013 | 25 views

Check the fuel filter and the fuel pump. Also check fuses.

Lexus LS 400... | Answered on Sep 08, 2013 | 26 views

Which fuse??

Lexus LS 400... | Answered on Aug 13, 2013 | 40 views

Look wireing harness that is close to it and strip the tubeing from or tape and see for a broken wire

Lexus LS 400... | Answered on Apr 02, 2013 | 166 views

it's an extremely hard thing to do without a diagnostic computer, because you need to see its reading compared to other variables while the engine is running.

Lexus LS 400... | Answered on Mar 03, 2013 | 18 views

battery and connection,spark plugs,fuel filter,air filter,starter.

Lexus LS 400... | Answered on Feb 26, 2013 | 99 views

Well I would first ask why you would want them on. The computer grounds the fan relay when the fans are needed.
They don't run until the ac is on or the engine reaches 220 degrees.
Sometimes smoke in the radiator is a sign of a leaking head gasket.

Lexus LS 400... | Answered on Oct 01, 2012 | 81 views

The code for the sensor is the giveaway.
The computer does not know how much fuel to give the injectors without that sensor working. The computer uses a factory set default reading.
Assuming the cooling system is full of fluid, you should be able to test the circuit and the sensor with a meter and a scanner. The sensor is a resistance variable that takes a 5 volt reference from the computer and changes it depending on the resistance in the sensor.
The sensor should read different resistance at different engine temps, and the harness should carry the voltage back to the computer. The scanner should show the sensor reading as the engine warms up.

Lexus LS 400... | Answered on Sep 25, 2012 | 530 views

The Engine and Automatic Transmission (not applicable to manual transmissions) in this vehicles drive train are fully electronically controlled by a computer called the PCM and TCM (Power Train Control Module, Transmission Control Module). When a problem like this or other drive-ability related problems occurs the computer stores a record of the problem (there are of course some exceptions to this, like the fuel pump, engine coolant temperature sensor and MAF sensor for instance) in the form of a fault code in its memory, to read these fault codes you must have the systems memory scanned with a special tool. Once the fault code(s) are read you then must perform the appropriate diagnostic testing to find and resolve the problem(s) DO NOT REPLACE ANY PARTS UNTIL A TRAINED TECHNICAIN HAS DIAGNOSED THE PROBLEM TO AVOID SPENDING YOUR HARD EARNED MONEY ON PARTS THAT MAY NOT CORRECT THE PROBLEM. Also always check fuel pressure for correct spec for your make and engine type.

Lexus LS 400... | Answered on Sep 11, 2012 | 102 views

Then a problem is occurring in the system, have the dealer scan it and see what is keeping it from starting. It may not be the alarm system, other problems may be occurring.

Lexus LS 400... | Answered on Sep 04, 2012 | 625 views

The voltage regulator for the alternator is located inside the rear housing of the alternator. It can only be accessed by removing the alternator and dismantling it. If the regulator is faulty it is repair by replacement usually by swapping for an exchange unit from an auto electrician. If the alternator is not charging it may just be a case of the brushes inside the alternator being worn out and requiring replacement.It will still be required to remove and dismantle to carry out their replacement.

Lexus LS 400... | Answered on Aug 27, 2012 | 443 views

I'm pretty sure only Ford products have a safety switch for the fuel pump.

Lexus LS 400... | Answered on Aug 27, 2012 | 312 views

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