RX300 (2001) P0325 - Knock Sensor

[trevlacuk]

My RX300 (2001) has done 103,000 miles and recently lit up the MIL engine warning light. And the car refused to go into OverDrive...!

My cheap eBay OBDII scanner showed the "P0325 - Knock Sensor 1 Circiut Bank 1" fault code.

Not having the time or energy to swap the Knock Sensors myself, and the garage bill to do the job, running into more £ that the car was worth, I needed another solution (other than my mates suggestion, which was black insulating tape over the offending light)

Thanks must go to Bobster999 and cwsteini  from the American 'ClubLexus.com' for their instructional hack.

Obviously, our RHD RX300 has a slightly different layout than the American LHD version, but they are basically the same...

Locating the ECU, behind the glove box, I had to drill out the bolts of the tamper-plate because I didn't have the right star-key to undo them :-( 

(Strangely, the American RX300 doesn't have this tamper plate to stop them getting to the ECU)

The Knock Sensor wires are in the bottom connector (Black for Knock Sensor 2 and Clear for Knock Sensor 1)

Because my Knock Sensor 1 was at fault, I cut and connected both Black and Clear wires from the ECU to the Good Black wire from Knock Sensor 2 .

This took about 30 minutes from start to finish, and now, 125 miles later, the fault code is still cleared, there are no warning lights on the dash and the car drives beautifully smooth and now goes into overdrive, as it should...!!!

Now I know this is not a 'proper' fix, but has kept my lovely 16 year-old Lexus going, hopefully for long enough to give me a chance to save up a big pile of cash, to get both Knock Sensors changed, when number 2 sensor eventually goes (hopefully NOT soon)

I will stick a few pictures, below, to show what I did.