From: james.steelman on
Just got a check engine light on my 2000 3.0L Sienna Van. The nice people at
AutoZone pulled the DTC code and found a P0155 O2 Sensor Heater Circuit
Malfunction (Bank 2 Sensor 1).

Is this a big problem or a little one to fix? Am I looking at a $50 or a
$500 fix? I get the impression that the car is Ok to drive for a while with
the possible loss of some fuel economy. Is this correct?

TIA, Jim
From: Ray O on

<james.steelman(a)gmail.com> wrote in message
news:JwrDg.575$n8.338(a)newsfe04.lga...
> Just got a check engine light on my 2000 3.0L Sienna Van. The nice people
> at
> AutoZone pulled the DTC code and found a P0155 O2 Sensor Heater Circuit
> Malfunction (Bank 2 Sensor 1).
>
> Is this a big problem or a little one to fix? Am I looking at a $50 or a
> $500 fix? I get the impression that the car is Ok to drive for a while
> with
> the possible loss of some fuel economy. Is this correct?
>
> TIA, Jim

This is a moderate problem to fix, probably around $300 for a dealer to fix,
about half that if you buy the part and replace it yourself. The car is OK
to drive for a while with the problem.

If you want to fix the problem yourself, the first step is to check the O2
sensor heater circuit. For $10/day, you can access the factory service
manual at techinfo.toyota.com and you can download the section on checking
the O2 sensor heater circuit. You will need a volt/ohm meter to do the
check. I'm pretty sure that Bank 2 is the front side of the car, and the O2
sensor will be a silver cylindrical thing sticking out of the exhaust
manifold with some wires connected. If the O2 sensor heater circuit tests
bad, you can go to your local Toyota dealer, purchase the part, and replace
it yourself. Replacement require unscrewing the old sensor and screwing the
new one in and replacing the connector.
--

Ray O
(correct punctuation to reply)