Solving P1166 error code

CRXEE8 · Post by **CRXEE8** » Wed Dec 27, 2006 9:55 am

I'm trying to solve a P1166 error code in my track car. I'm using a PRB ECU and I have made my own wiring harness. I have rechecked the wiring for the RSX wideband O2 sensor several times and I'm 100% sure it's right. The thing that might have caused the problem is that I wired the O2 heater relay wrong so E8 got 12V. I have rewired the relay and I'm getting 0V with the ignition on as it shall have.

1. Which IC might be dead in the ECU? I have traced E8 to IC181 so I'm thinking that's it?

2. If I disable the O2 heater in K-Pro should I then be able to read the O2 current? I still just get -37 mA, 10.7:1 A/F and 0.0 V. I have tried to datalog it and it does not change. I'm using ITB and the 48 mm ITB alpha N map in this datalog.

Post by **Hondata** » Wed Dec 27, 2006 10:21 am

First try your ECU in another vehicle with known good wiring (stock is best) to find out if it is the ECU, wiring or o2 sensor.

The o2 sensor will not work if the o2 heater is not working. I have not traced the heater circuit on the PCB, but IC181 looks like the right sort of IC.

CRXEE8 · Post by **CRXEE8** » Wed Dec 27, 2006 12:41 pm

The O2 sensor is brand new and I have rechecked the wiring both with the wiring diagram i the tech section and in the Helms manual.

Do you mean the O2 heater in the sensor or in the ECU? I can't see why E8 has anything to do with reading the O2 current because you don't even hook up E8 when you use the RSX O2 sensor in a CTR. Is it because the ECU goes in a mode where if it reads an O2 error then the other O2 signals won't be shown in KManager? I just hoped to disable the O2 error codes and still being able to read the A/F but I guess that won't work.