check engine light

[frazidlo]

New to the group today ...this may have already been discussed however...
For the third time this winter when after leaving my 2003 out in the cold overnight (+10 F or so)
multiple warning lights come on when starting the vehicle. These include the "check engine " light,
a triangle warning light both up by the odometer area as well as a warning display where the milage would
normally be showen. The first time this happened (actually last winter ) I sched. an appoint. with the
dealer however the problem "fixed itself" that same day and I cancelled the appt. I didnt give it much
thought till this winter when the problem returned. As it has cont. to "fix itself" within a day or less and the
car seems to run fine even with all the lights lit I've hesitated to bring the car to the dealer...the car has 70,000
trouble free miles otherwise. Should I bite the bullet and take the car in or is this some cold weather glitch
that results in "no harm done" and cont to ignore?? thanks Raz

[eagle33199]

I don't believe any sort of glitch has been discovered...

There could be a problem with your car that only manifests itself when it's really cold (a night of sitting out will do that - and since days are warmer, the problem seems to fix itself during the day). If the conditions for a CEL go away, then 3 restarts of the car will clear the light, although the computer will retain the codes so the dealer can diagnose the problem. If it were me, i'd take the car in... the problem may be small and infrequent now, but it could lead to something big and more expensive later on.

[tochatihu]

Hi Frazidlo, all 2001-2003 Prius are subject to a cold starting warning light as you have seen. I do not believe that there is a copy o ftechnical service bulletin EG011-03 posted to Priuschat, so here it is.

The most common repair requires only the replacement of the engine control module (ECM). This is under warranty for 80K miles. If the other two parts are required (much less frequent), you will pay.

In general experience, once the ECM is replaced, the problem does not recur. I have no explanation why Toyota continued putting ECMs with 'bad programming' into Prius, as late as 2003.

[frazidlo]

<div class='quotetop'>QUOTE(tochatihu @ Dec 9 2006, 11:15 AM) [snapback]359738[/snapback]</div>

Hi Frazidlo, all 2001-2003 Prius are subject to a cold starting warning light as you have seen. I do not believe that there is a copy o ftechnical service bulletin EG011-03 posted to Priuschat, so here it is.

The most common repair requires only the replacement of the engine control module (ECM). This is under warranty for 80K miles. If the other two parts are required (much less frequent), you will pay.

In general experience, once the ECM is replaced, the problem does not recur. I have no explanation why Toyota continued putting ECMs with 'bad programming' into Prius, as late as 2003.
[/b]

Thanks...will be seeing dealer tech on wed. and will share the info with them. i will let u know , raz