I have a 1999 Rx300. It was running fine last month but it wouldn't pass the smog check. The CEL kept lighting up and the codes P1155 And P0171. And now the battery the car is just burning the battery. I think it might be the ECU but im not certain, any idea what it could be?

 

Welcome to Club Lexus!

What do you mean by the car is just burning the battery? The code is for a oxygen sensor.

 

Car batteries are relatively cheap. Have the charging system and the battery tested at any auto shop that sells batteries.

Was any thing done to the RX that might have created the battery problem?

Salim

 

Salim,
thanks for the tip. and nothign was done to the rx that we think could have created this problem

 

hypervish,
thanks for the welcome. the oxygen sensor was changed but the battery looses all the charge within 5 to 7 min. and it wont recharge them. i switch batteries 3 times already and the same problem continues

 

Would appear to be a short somewhere. Usually in the starter or alternator circuitry when its that bad. Surprized it isn't sparking all over the place if it's draining the battery that fast.

 

So you are either not getting charged by alternator or there is a load that is bad. Do you have any aftermarket accessory? My second suspect would be the alternator. To find out a bad load, you can pull the fuse out. 7 minutes to discharge a good battery, is pretty horrendous load.


Salim

 

If you can discharge a fully charged battery in 5 to 7 minutes, there must be a whole lot of smoke rolling there somewhere, unless you are using flashlight batteries in it. That's just CRAZY!