Mechanics

IGNITION FUSE BLOWS 30AMP NO START

1993 Toyota Corolla

Electrical problem
1993 Toyota Corolla 4 cyl Front Wheel Drive Automatic 180000 miles

1993 toyota corolla dx wagon does not start.
Stalled while driving, has not started since.
Ignition fuse blows.30Amp in engine bay.
Checked for shorted wires, could not find.
Disconnected alternator and starter, still blows fuse.
disconnected distributor, still blows fuse.
Checked starting switch, 0.5 ohm
checked distributor
coil 1ary resistance 1ohm, secondary, 11kohm
pickup coil, says.200 and.400(G-G+ and NE-Ne+)
checked Te1E1 diagnostic, no check engine code at all.

Is it a bad relay. Tomorrow I go to junkyard to get relay, fuse box, distributor and more 30 amp fuses( blew 10 already testing).
Will appreciate any fresh ideas. Thanks.

ps. Had an aftermarket alarm; discoinnected all spliced in wires and reconnected ignition key cable that was cut to install alarm. Alarm is a chapman(probaly 10 or more years old).
ps2. Now the fan turns on(and of course coolant is cold, since it won't start)

Someone suggested I check the radio for a short there( thanks for the idea). I will check that.
It makes sense. I already had a similar electrical problem with another car. I was installing a stereo and when I turned on the ignition, it would start blinking on and off. Turned out to be that I forgot to untie some cables I had shorted in the turn signal light( I was repairing the left fender and the cables were tied together).

ps. Forgot to mention the starter is working. Turns engine. But no spark in plugs(tested with those flashing spark cable light tester).
could not check if fuel is sent because the fuse blows.
How can I test fuel pump ( maybe disconnect and send test lead to +.
How could I test if starter has a relay that is no working right( does it have a relay inside the startert unit?)
Any more ideas are welcome(im already at the point of bANGING MY HEAD TO A WALL)
Avatar
Tangopampa
June 16, 2009.



Remove alt. And starter and have them bench tested at most autoparts stores.

The fan running all the time is a bad fan switch.

The fuse is most likely (if alt. And starter are OK) a short to ground in the wiring and can be difficult to isolate.

Mmprince4000
Jun 17, 2009.
Checked fuel pump cables too. Disconnected pump. No luck yet. I am going to test the starter and alternator( I am doing that right now).
By fan swith, is it the coolant temperature sensor or some switch inside the fan armature?
I forgot to mention that I also disconnected the fan too( no luck, still blows the ignition fuse.

Tiny
Tangopampa
Jun 23, 2009.
Fan switch is on side of head in a coolant housing. It s usually a white connector that points toward the drivers side shock tower.

Inspect all wiring for any burn marks and exhaust system for any leaks. Exhaust leaks can quickly burn wiring.

Mmprince4000
Jun 24, 2009.
Thanks for your response.
I checked for charred cable or leak from the exhaust; no luck.
I have been tracking the cables :
black with red( AM2)
and black with orange( to the injectors).
I have been tracking the AM2 from the fuse box onwards.
I have been tracking the injector cables from the injector side onwards, and from the ignition side onwards.
have not had any luck so far.
i am stuck since I have almost eliminated every circuit.

ps.
disconnected every relay and fuse except the one I mention below.
tested injectors and they have the resistance shown in repair manual
disconnected EVERY fuse( except the three big ones: AM1-start,airbag-, ALT100A-tail,stop,ECU-B,AM1,ABS- ,and ABS50A -abs- )and it blew again.
Starter and alternator are new. I changed them. I wanted a reliable starter and alternator(that is when the car starts).


http://www.2carpros.com/forum/automotive_pictures/370042_toyota93Engine_1.jpg


Tiny
Tangopampa
Jun 30, 2009.
Ign switch and fuse box inside


http://www.2carpros.com/forum/automotive_pictures/370042_Toyot93IgnSwitch_1.jpg



http://www.2carpros.com/forum/automotive_pictures/370042_Toyot93FuseIn_1.jpg


Tiny
Tangopampa
Jun 30, 2009.