Hey Guys -

So, couple quick questions. I hit up AutoZone for a OBD II scan and the code pulled up I *believe* P420. That is an O2 sensor, correct? Is that enough information to find out exactly which of the 4 I need to replace? Please advise. Also, is there a part # for what I need to buy? They had the OEM 02 (Bosch) and the universal as well - OEM was $112 and universal was $66.


Second question. A/C Diagnostics. Ran a search and couldn't come up with a solid answer for my GS400. So, I hold down the Auto and the Recirculate button and I get one of two things. I get the 0-9 level check where it increase/decreases fan speed and changes the setting or I get one of the settings that blinks and I get a 0 blinking in the upper left box. Am I doing this wrong? My A/C does not work properly so I *should* be pulling a code of some sort. Any advice on this? Both of the responses I get from the diagnostic (the speed/setting check and the 0/setting button flash) just continue over and over and I get no result.


Thanks for the help on these guys!

 

No answers for either of these?

Any help is appreciated! Thanks guys

 

bump for any help on these two issues.

 

I have a service manual for 98. I use it to work on my 01. The code will take you through a trouble tree to make sure the wiring is ok and the ecm is ok before deciding on the sensor. Usually the code corresponds to one of the four sensors. You can use an ohmeter and if you have one that reads temperature with a probe or infrared you can do another part of the test where you have to have a certain exhaust temp and then check the resistance at the sensor in question. I am away, but can look up the code and trouble tree when I get back if that will help. I got into all this because I took it to a local shop and they just said all my sensors needed to be replaced and it would cost $2000 or something ridiculous like that. I said screw that, I can diagnose it myself the bastards! It did end up being a sensor, which I purchased at park place lexus in texas.

 

Good info. I don't have an ohm metere with temp unfortunately. Is there no way to narrow it down other than that?