Intermittent warning lights

[Sedanades]

My 2007 sedan has been flashing various warning lights intermittently.

Two weeks ago when there was still snow and ice where I live, the ABS/BRAKE lights stayed on after starting, and the ABS would no longer work. I drove over an ice patch to verify. Numerous key on/key off attempts didn't change anything.

The following day the ABS/BRAKE warning lights stayed off, and have remained off since.

Yesterday I noticed the Battery light remained on after starting, then went out after a couple of minutes. Today I noticed the Battery light and the Airbag light flashing on and off intermittently while driving.

Might all this be a loose plug connection somewhere, or something else? I've owned the car 2 years without any similar problems. I noticed the cover to the fuse box wasn't snapped tight, for how long I can't say.

[09sedan]

for abs lights, go to your mechanic, have him lift the car, unhook the rear abs connectors, try to clean them with electrical contact cleaner, then spray some electrical contact grease , (yaris prior to 09 had problems with their rear abs harnesses letting water/salt in which caused the connector to corrode) if your lucky that will solve problem if your not then you will have to replace the harness on whichever side is corroded ( or both) which can cost more then 500$. for the airbag light , check your battery terminals to make sure they are not corroded and are on tight, check your battery voltage when car is off it should be :

Battery Voltage and State of Charge:

12.68v . . . . . . . . . . 100%
12.45v . . . . . . . . . . 75%
12.24v . . . . . . . . . . 50%
12.06v . . . . . . . . . . 25%
11.89v . . . . . . . . . . 0%


(NOTE: these readings are at 80 degrees F. Battery voltage readings will
drop with temperature roughly 0.01 volts for every 10 degrees F.)
(At 30 degrees F. a fully charged battery will measure about 12.588 volts, and at zero degrees F it will measure about 12.516 volts.)

while your car is on check voltage and it shud be between 13.5V and 14.5V if below 13.5V your alternator is not outputting enough as it normally should.



if ur fuse box cover was open,check your fuse box terminals and check all your fuses and the box itself for corrosion. also check your ECM connectors and see if it looks corroded or not.

hope that essay helps.

[Sedanades]

Thanks for the info.

After shutting it off the battery can read up to 13.5v

When running, voltage fluctuates around between 15.5v and 16.4v - so the voltage regulator must be kaput.

[BLH]

There are threads here on the 2007 Alternator having a corrosion problem on the built in voltage regulator.
http://www.yarisworld.com/forums/sho...05&postcount=2

[Sedanades]

I took it to the Stealership today (I have an extended warranty) and of course the tech finds that the alternator is operating properly. I explained the flashing warning light, overvoltage, headlights dimming and brightening, that it is intermittent. It acts up only when the mechanic isn't running a check. :^(

So I'm letting them keep it overnight and drive it on errands to try to replicate the problem. I'm thinking I'm going to end up replacing (or cleaning) the regulator myself.

[jp_costarica]

Hi Sedanades, did you fix this issue?

I have same symptom with my y07.

[CTScott]

If the alternator and voltage regulator within it seem OK, another possible cause is corrosion of the connector where the large wires connect to the positive battery terminal block.

[Sedanades]

Hello jp -

From April to now it acted flawlessly. I gave credit to warm weather. Lately, it has been running overvoltage after starting, then it settles down.

I removed the alternator, disassembled the regulator and brush assembly, sprayed DEOXIT on all the contact points, reassembled the thing and bolted it back in the car.

No change. Grrrr.

Thanks for the idea CTScott, I will try that. Just follow the wire from the alternator to where it ends?

[CTScott]

Originally Posted by Sedanades

Hello jp -

From April to now it acted flawlessly. I gave credit to warm weather. Lately, it has been running overvoltage after starting, then it settles down.

I removed the alternator, disassembled the regulator and brush assembly, sprayed DEOXIT on all the contact points, reassembled the thing and bolted it back in the car.

No change. Grrrr.

Thanks for the idea CTScott, I will try that. Just follow the wire from the alternator to where it ends?

Yes, you can follow the wire up, or pull off the positive battery terminal and you will see where it connects to on the bottom of it. If you are seeing over voltage, then it isn't corroded contacts, but rather a bad regulator.