Toyota Previa 2.4 2001 - 30amp fuse keeps blowing when engine started #
Posted by George Georgiou on November 17, 2011, 11:58 pm
Year of Manufacture *: 2001 Engine Size and Code *: 2.4 PETROL
Not had a chance to get my mits on this one but as I like to go to a job with some useful test plan to not waste time I tried to look up some info on this problem and found very little to go on.
Customer reports that a Fuse value 30 amp keeps blowing when engine started and runs for a few minutes from cold , after which if fuse is replaced engine only runs for a few seconds before blowing again.
This suggests that something is warming up and either creating a short e.g O2 sensor wires touching a hot exhaust, or something like a motor or fuel pump getting hot and drawing excess current.
Fuse is located in position AM2-2 in main engine fuse box and is 30 Amp toyota square type.
Does anyone have a circuit showing what elements are powered by this fuse or a description of what is fed from this fuse.
From web sources it may be feeding into ignition switch and then powering ignition/fuel injectors i.e part of main engine loom which would make sense if something is shorting on engine.
Help please....
Re: TOYOTA PREVIA
Posted by aidan birley on November 18, 2011, 8:08 am, in reply to "TOYOTA PREVIA"
George
If no one comes up with a wiring diagram, Auto data tech help should have the information.
Posted by Kevin Apps on November 18, 2011, 10:28 am, in reply to "TOYOTA PREVIA" Kevin Apps
George
e3 technical.
Kev.
Re: TOYOTA PREVIA
Posted by Iain MacCormick on November 18, 2011, 8:36 pm, in reply to "Re: TOYOTA PREVIA" Iain MacCormick
George
Just mailed some info.
HTH
Iain
Re: TOYOTA PREVIA
Posted by GEORGE GEORGIOU on November 24, 2011, 11:09 pm, in reply to "Re: TOYOTA PREVIA"
Iain thanks again for the wiring diagrams , for now it been several days without a fuse blow and if it starts to play up I will use the info provided.
I went out to the job before I had the diagrams so was working blind and managed to blow up 3 or 4 30 amp fuses after wiring the fuse holder to accept standard fuses. A lot cheaper than the Toyota fuses. I got a bit bored so moved into danger territory and also managed to pop a 40 amp fuse just to see if it might run with a higher rating.
It would seem from the diagrams that almost everything to do with the engine is serviced by this fuse inlcuding injectors, coils ,4x O2 heater circuit, EFI relay, immobiliser, fuel pump power, idle control valve, airflow meter, radio and the ECU itself.
This car had new exhaust manifold fitted a few months back and 4 new Toyota O2 sensors. I disconnected all 4 sensors placed another 30 amp fuse and engine started, however it did not blow on reconnecting all 4 sensors back up one at a time so none the wiser except possibly to rule out the sensors themselves.
I isolated the starter relay by removing it and power probing it to turn it over which was OK . But when fuses were blowing it would seem that almost within a split second of turning the engine over with the power probe the fuse would blow which strongly suggests an ECU commanded control signal switching on a sensor or a solenoid e.g injectors or coils or anything really!!
For now I reckon the 40 amp fuse has blown the short clear somehow as the owner (taxi driver) has not come back to me on any further problems. I suspect this is a wiring short on an engine loom somewhere as once started it runs and drives OK.
I'll look into the e3 Technical as I need to have more info than Autodata. Autodata technical did verbally tell me how this fuse was connected but for some reason could not send me the info as it was their original info? All I needed from them is to scan it and fire it over by e-mail, maybe copyright problem with them and Toyota perhaps?
on November 18, 2011, 8:08 am, in reply to "