My Abandoned Gs300

Mike246 · October 27, 2012

Oh dear. Oh dear. After 14 years and 165,000 trouble-free miles with my '98 GS300 it is sitting in the local supermarket car park awaiting recovery.

Got my shopping and loaded in the car. Went to start it and it failed to start. The engine kept turning on the starter motor even with the key out. By the time Lexus Recovery (the AA) showed the Battery was totally flattened the the starter terminals rather hot.

Simon, the AA man was unable to get me going but did all the right things and importantly, was able to diagnose that the fault is in the starter motor itself, rather than a short in the ignition switch or starter relay.

Tomorrow I'll get the car recovered and down to the local Lexus dealer.

I guess the answer is a new (maybe it's an exchange) starter motor which should double the value of the car! Any related experience or guidance would be most appreciated.

steve2006 · October 27, 2012

It does sound like the starter motor has failed, if the solenoid plunger jams this also keeps the contacts closed to the motor and it will operate continuously even with the ignition key removed.

Hopefully no damage has occured to the flywheel teeth and all that will be needed is a replacement starter motor and a good Battery recharge.

Given the age and value of the car it may be worth considering a local independent garage to do the job which would be considerably cheaper than Lexus will charge you and get a remanufactured starter instead of new.

At least it's not an LS400 where the inlet manifold has to be removed to even see the starter motor.

TigerFish · October 28, 2012

Does sound like the starter. Unusual it went from fine to sticking on straight away. They tend to go through a period of just clicking and not starting, which is the tell tale sign. They can be repaired easily, even DIY (there is a link in my sig to a tutorial I did). The dealer should be able to overhaul as I believe they can source the parts for an overhaul too.

Mike246 · October 28, 2012

Thanks guys for your valuable input.

Tigerfish, it did go through a period of just clicking and I was able to start it be giving the selector a wiggle between Park and Neutral. Therefore I thought it was the Neutral Start (Inhibitor) Switch that was playing up. I do not have the circuit to hand but I don't think a faulty Inhibitor Switch can cause the starter to continuously run.

From what you have posted, the Inhibitor Switch is just a red herring . . . . unless I have two faults!

I'll speak to the dealer in the morning about cost of the motor replacement vs possible overhaul.

TigerFish · October 28, 2012

Yeah, I don't have the circuit diagrams to hand either, but I would expect that the inhibitor would only interupt the supply to the relay for the solenoid. Once the solenoid is thrown, the starter itself takes power direct from the Battery through the contact that the solenoid makes. It is the solenoid sticking on that keeps the starter cranking even after the ignition is switched off.

Mike246 · October 29, 2012

Popped into the dealer and had a chat with the service advisor. An exchange starter motor is £ 213 which is not so bad as it comes with a 1 year warranty. The dealer did not want to get involved with an overhaul kit, even though I would be comfortable doing the work on the motor myself. No surprises there.

Either way I would have to pay for 1.5 hours' labour in removing/refitting the starter so I'll let them get on with it. The car may not be worth much (two have gone with less mileage than mine on e-Bay recently at less than £ 1,000 each) but it just sailed through the MOT and runs great. Very little has needed replacement in 14 years' ownership so I can't feel hard done by!

Dealer is Lexus Hatfield who are always nice to deal with and honour the LOC discount.