Lexus IS 250 2006

[gord1954]

Hi I'm new to this so please forgive any mistakes, I bought a secondhand is 250 se- l had problems with it soon after I bought it.. the company I bought it from have gone into liquidation so no joy there... the electrics started to play up within 2 weeks of purchase.. I took it to an independent garage who diagnosed first the alternator then the ecu they replaced the alternator no change .. so I sent the ecu off it was tested and found to be fine.. electrics not my strong point.. what was happening was that the electrical systems started breaking down one after the other then the car wen into limp mode.. anyone had this problem? Or any ideas what could cause this?

thanks in advance 

Gordon 

[Shahpor]

Hi Gordon,

I know what you mean;  car electrics scare the life out of me

Have you tried replacing the Battery?  It has been known to through up all sorts of random errors when it gets weak.

Also, has anyone tried to read the fault code from the ECU?

If not, then that is where I would recommend to start.  You can get a fault code reader cheap enough from eBay which should give you the code.

Even if the 'Check VSC' message isn't currently on there is a good chance the ECU has stored the code.

If you can get that, it will help diagnosing the problem much simpler.

[is200 Newbie]

Agree with Shahpor - code reader would be your first step to see if it reveals where the issues lie

But - what were the issues you were facing?

[gord1954]

Thanks guys for the response.. the car has had a new Battery and alternator also the ecu was sent away to be checked no problem was found with either the hardware or software on the ecu.

the problems started as one by one things ( electrical) started to go down from the sat nav.. reversing camera the exterior mirrors would not fold in... basically everything electrical started having problems then the car would not start the dash went dead... the garage who checked the car out said it must be the ecu but that has now been tested and found to be perfect... I'm lost on what to do next.

Gord

[is200 Newbie]

Has it had a new windscreen? (water getting into the cabin)

Check out the fuse boxes for water damage anyway - there are quite a few -

[gord1954]

No new windscreen as I'm aware of.. but reading up on things I'm wondering if it could be the alternator fused link 150 amp? seems it can cause some of the issues I've had.

Gord

[Linas.P]

A bit random advice, but check main ground cable connection. It can corrode and make various issues, otherwise just clean all contacts (especially on Battery clams), clean contacts on fuses. 

OBD2 scanner is great thing, but it will be very difficult locate electrical problems with OBD codes..

[gord1954]

Thank you for your advice I'll check it ot

[gord1954]

Nothing on the OBD I tried one of the cheap Battery alternator testers ( like I said I know next to nothing on car electrics ) but it registered nothing from the alternator I tried it on my sons car every thing came up normal? I tested it on my Battery before starting my Lexus and the Battery read fine fully charged but once running nothing from the Battery or alternator? 

Anyone any ideas please I’ve had the car into a garage who thought it was the ecu I sent that away for testing nothing wrong with it...the garage said they had the alternator tested and it wasn’t good so they had it reconditioned they are puzzled.

any input would be more than welcome as I’ve had the car six months and surprise the garage I bought it off went into liquidation..just my luck.

thanks Gord

[Shahpor]

So no fault codes stored?

Do you have a multi meter?  What I suggest is checking the voltage output of the Battery and alternator.

Before starting the car, put the leads on the Battery and check the voltage, it should read above 12v.  Then start the car and put the multi meter leads on the connectors that attach to the Battery.  It should read over 13v but less than 15v.  While the car is still running, turn on as many electrical items as you can eg. lights, air con, rear demister, wipers, etc.. and check the voltage again.  It needs to read over 13v but have dropped slightly.

This indicates whether the alternator is providing enough voltage to power the car and charge the Battery.  Checking the voltage on the Battery before starting it should also tell you whether the Battery is holding a correct charge or not.

Failing any of this, your best bet would be an automotive electrician.

[is200 Newbie]

Is the Battery getting warm/hot?

There is a Battery sensor attached to the side that I think may shut the system down if it thinks the Battery is getting hot - or something along those lines.... anyway it wont cost anything to check and will rule out one scenario.