2000-4Runner

Hello all,

I would appreciate it if somebody could help me with my problem. A couple of months ago my cat converter was stolen, together with both oxygen sensors. The thieves just cut the oxygen sensors wires taking the plugs with them and leaving me with a doubt of which cable goes where.

I have been looking around online for a ECU wiring diagram which shows me the color coding of the cables that go into the oxygen sensors (4 wire sensors) with no luck. It is easy to find those that go into the heater as they have 12 volts, but I'm affraid I may screw it up and burn my new oxygen sensors.

I have only found the electrical diagrams for the 5VZ but not for the 3RZ, which is the engine my Runner has.

Please help! my fuel economy will thank you!

Jay204

man that sucks, someone on here must have some info for you, hopefully you can get that sorted out.

97ltd4x4

From my 97' EWD,3rz-fe engine control..
With the O2 disconnected, looking at the O2 sensor with the locking tab at 12 O'clock..like this:

pin locations,looking at the connector:
Tab,12o'clock
___/ \___
1 2
3 4
________

1:top left,2 top right,3 lower left,4 lower right

for bank1,sensor 1..(sensor closest to engine)

(pin symbol)pin: wire,from body harness:

(th)pin1: P(solid pink)
(B+)pin2:W-L(white with light blue stripe)
(OX)pin3:W(solid white)
(E1)pin4:BR(solid brown)


bank1,sensor2

(th)pin1:R-W(red with white stripe)
(B+)pin2:W-L(white with light blue stripe)
(ox)pin3:R(solid red)
(E1)pin4:BR(solid brown)

th=heater,B+=batt voltage,OX= oxygen feedback signal,E1=ground



If these colors are off,The pin locations should be the same.swing by your local dealer and ask the to print you off the pages for the 3rz-fe enging control EWD pages from there TIS machine.I am sure if you tell them what happened they would help.

Man,that really sux what happened,I hope this will help if not get you going in the right direction.

2000-4Runner

Thanks for your wishes and help! actually, the colors you mentioned are similar to the ones found on the service manual for the 2000 Runner. My problem is that the cables I found dont match those in the service manual! .

My other problem is that I'm located in a place where there are no friendly Toyota dealers, they tend to have a "You didn't buy it from us, we don't have to help you" policy.

I have found the following cables:

front oxygen sensor:
1 brown cable (this one would be OK)
1 red cable (????)
1 red cable with a white strip (???? the colors on this one correspond to a rear oxygen sensor cable)
1 white and green cable (????)

rear oxygen sensor:

1 white cable (???? this one would correspond to a front oxygen sensor cable)
1 black cable (this one would be OK)
1 red cable (again: ????)
1 white and green cable (the same as in the front ????)

I found some info on the Service Manual and hopefully I would have time to check tomorrow if the cables going into the ECU match the colors of the ones found.

Would it be possible that, due to some unknown reason, Toyota decided to change the colors of the cables? (eg. the white and green cable would correspond be replacing the +12V white cable with a red strip and the red cable the brown ground cable).


Thanks again for your help!

SchooBaka

Are they Toyota O2 sensors or after market?
Toyota sensors should come with a connector.
As for the color of the wires, they will change from one side of a connector to the other. If you don't have the connectors, you might try finding some at a junkyard; if they're aftermarket O2's they should tell you how to wire them to the factory harness.

2000-4Runner

The colors I'm mentioning are those of the cables I found under the SUV, the cat thieves took the vehicle O2 sensor connectors with the cat .

The replacement O2 sensors I'm buying are Denso (I read everywhere that I whould stay away from Bosch) and they come with the correct Toyota connector but, as I mentioned, the connector from the vehicle side is missing, that is the reason why I´m trying to figure out the color coding.

Thanks for the help given!

97ltd4x4

You "might" have an O2 sensor and an A/F sensor,not just two O2's.....On both the O2 and A/F-A/F and A/F-O2 systems,there are some common wires...With all systems,they all share the same 12+ wire colors....So I think your White-Green wire being 12+ for both the sub1 and sub2...

Also they all use shielded wires for the OX,pin3(will have fine meshed wire strands wrapped around inner wire insulation)...(most likely black wire on sub2 sensor)..not sure about sub1

Thats 4 out of 8 there half for sub1-2...

Most likely the sub2 is an O2,not sure,but you could do an OHM check w/meter to find out...And if that the case,you will know 3 out of 4 wires for sub2..and the last unknown wire would be heater.

If you could get the pinout of the ECM,you could verify this...Also you could determine if Sub1 is an A/f or just an O2..A/f will be grounded through ECM instead of chassis ground like a regular O2 sensor.

An EWD would really help,maybe check Ebay?...or bribe the writer at your local dealer with some donuts?...LOL

2000-4Runner

97ltd4x4 you were right! When I got this truck I didn't have any reason to suspect it was a CALIFORNIA 4-Runner (I don't live in CA) and, as you supposed, it uses an A/F sensor in the front. I could have used 1000 oxygen sensors and it still wouldn't work!.

Anyway, I got an EWD for the vehicle (the ECU is VERY different from the standard Runner, at least the connectors). What is very strange is that the cable colors are all off from the EWD, I had to use an Ohmmeter between the ECU connector and the sensor connector (unplugged so I wouldn't inject any voltages into the ECU) and check the connections. Here is what I found in case anybody else has the same cable coloring scheme (I'm stealing the ASCII diagram from 97ltd4x4, I hope he doesn't mind):

___/ \___
>
1 2
3 4 >
________

1:top left,2 top right,3 lower left,4 lower right

for bank1,sensor 1..(sensor closest to engine) - A/F SENSOR FOR THE CA RUNNER

(pin symbol and location in ECU connector)pin: wire,from body harness:

(HAFL, pin 4 of C connector in ECU)pin1: R(solid red)
(B+ (Battery +12 Volts))pin2:W-B(white with blue stripe)
(AFL+, pin 11 of C connector in ECU)pin3:B(solid black)
(AFL-, pin 20 of C connector in ECU)pin4:W(solid white)

bank1,sensor2

(HTS - pin 3 of C connector in ECU)pin1:R-W(red with white stripe)
(B+ (Battery +12 Volts))pin2:W-B(white with blue stripe)
(OXS pin 10 of C connector in ECU)pin3:R(solid red)
(E1 (Goes to ground))pin4:BR(solid brown)

Now, if I don't have to follow CA emission regulations (as I don't live in CA), would it be better to sell this truck and look for another one? or, besides the fact that I can get an O2 sensor for 70$, but an A/F sensor is now going to cost me 143$ I'm not going to have many other problems/price differences between a CA and a non CA truck?.

Thanks to all who offered help!