PDA

View Full Version : o2 sensor?


makulit054
09-25-2007, 08:09 PM
Can someone tell me what the wiring diagram is for the red top o2 sensor. I know which pin the signal wire goes to. What about the heater circuit. What pin is the 12v and ground suppose to be. I read some where that if the ecu doesn't detect the heater circuit then the o2 sensor circuit won't work correctly. I've traced my 12 volts back to the AC relay and the ground goes to the engine. The narrowband o2 sensor is suppose to be 0-1v but I get up 2.5 volts. I've replaced it with a known good but still the same voltage. I do have a LC-1 Innovate wideband. My afr's are 12-13. I just want to double check that my narrowband is wired correctly so my ecu will get the right signals.

UNISA JECS
09-25-2007, 08:24 PM
If you are running a redtop ECU which I assume you are hence redtop o2 sensor (which btw is a skinny type o2 not a fatty type) its doesn't use the 0-1v oscillating signal most of us are familiar with.......therefore im not even sure your innovative wideband could duplicate a red tops skinny o2 sensor readings from the ECU which im almost positive it cannot do. I just talked about this just the other day in another thread started by someone I look for it maybe it will help you undertsand the differences between teh skinny and fatty o2 and how and why the ECU are different in interputing o2 signals and why the o2 sensors are not interchangable.

makulit054
09-25-2007, 09:16 PM
Actually, you can program the LC-1 with different outputs. Besides, I've already contacted Innovate motorsports and one of the outputs is already set to 0-1v at the factory. Reading the FSM and the manufactures specs on the skinny o2 sensor, it's 0 to 1 volt. When the o2 sensor is heating up the voltage is suppose to be .45volts. Most o2 sensors have the same output voltages depending on whether it's a wideband or narrowband. I've seen people use the fatty type on redtops. Their stock ecu's had no trouble at all. Which pin is the the 12volts on the ECU coming from.

UNISA JECS
09-25-2007, 09:40 PM
Your incorrect on your last statement about the o2 sensors being swapable becasue they are not however im willing to bet yes people do run them that way but is is correct, no.

UNISA JECS
09-25-2007, 09:59 PM
Here is your proof of 0-1.5 volts this is a screen shoot from a Pulsar GTi-R SR20DET which only came equiped with the skinny o2 sensor just like the Redtop SR20's

Skinny o2 sensor now can you see the difference?
http://i167.photobucket.com/albums/u159/zilvia_album/SP32-20070924-231117.gif

http://i167.photobucket.com/albums/u159/zilvia_album/SP32-20070925-205358.gif

makulit054
09-25-2007, 11:29 PM
Looks like a misprint to me. This FSM EF & EC-373 states the ECU supplies the o2 sensor with 1volt and measures the o/p voltage depending on the resistance of the o2 sensor but EF & EC-625 states 0-1.5volts. The o2 sensor is more or less a thermistor/ temperature variable resistor which doesn't have voltage amplification properties. You input 1volt and you won't get more a 1volt drop across a resistor unless your supply voltage is greater than 1volt. Correct me if I am wrong about Electronic Theory. The other part of my thread was, what pin does the heater circuit come off on a #62 ECU?

UNISA JECS
09-26-2007, 12:26 AM
Dude you just first gotta understand there are two different o2 sensors types period. Its not a missprint look atthe top right hand corner do you see "SR20DET" this is actuall JDM RNN14 SR20DET manual which uses the skinny o2 sensor just the same as teh redtop S13 sr20det...........yea if you look at the USDM SR20DE or JDM S14 SR20DET you'll see 0-1volt refferened becasue all USDM OBDI and II and JDM Blacktop S13 and S14 (all) use the fatty type o2 sensor.

makulit054
09-26-2007, 03:13 AM
Dude read my first post and answer the question at hand? Are those two pages from two different manuals? I understand there are two types of sensors. I've already spoken with Innovate. I've given them my specs and yes the LC-1 wideband can be programmed to simulate a narrowband signal to the ECU. Not the LC-1 duplicate the skinny type o2 sensor readings from the ECU like you sated in your first reply. I understand your trying to help but your not really answering my questions.

UNISA JECS
09-26-2007, 09:52 AM
Those 2 pictures are from the same JDM manual. I know the LC-1 and LM-1 can duplicate a narrow band signal no doubt but what I am saying is the redtop ECU or for that matter any skinny o2 sensor ECU doesn't read like a common type fatty o2 sensor ECU, however both the fatty (Zirconia 95% common on a vehicles today) and skinny (Titania 5% common on all vehicles today if that).

Try calling Innovative and ask them what if you have a Titania based ECU that requires a skinny (o2 sensor/titania).

Here wikipedia explanes the difference of a few types of o2 sesnors:
http://en.wikipedia.org/wiki/Oxygen_sensor

and from another source thats explaines it here to:
http://www.aftermarketnews.com/default.aspx?type=wm&module=4&id=3&state=DisplayFullText&item=5589

"Titania O2 sensors use a different type of ceramic and produce a different kind of signal than zirconia type O2 sensors. Instead of generating a voltage signal that changes with the air/fuel ratio, the sensor's resistance changes and goes from low (less than 1,000 ohms) when the air/fuel ratio is rich to high (over 20,000 ohms) when the air/fuel ratio is lean. The switching point occurs right at the ideal or stoichiometric air/fuel ratio. The engine computer supplies a base reference voltage (one volt or five volts, depending on the application), and then reads the change in the sensor return voltage as the sensor's resistance changes. Titania O2 sensors are only used on a few applications, including some older Nissans and 1987-1990 Jeep Cherokee, Wrangler and Eagle Summit."

I put the o2 sensor wiring diagram of both types Titania vs Zirconia up in a minute.

Titania Sensor
*Terminal C = Power Supply (battery voltage)
*Terminal B = Input Signal (to ECU/shielding grounded to engine)
*Terminal A = Ground (to body ground)

This is ODBI style connector RNN14 SR20DET for Titania Heated oxygen sensor;
http://i167.photobucket.com/albums/u159/zilvia_album/SP32-20070926-090912.gif

Zirconia Sensor
*Terminal C = Power Supply (battery voltage)
*Terminal B = Input Signal (to ECU/shielding grounded to engine)
*Terminal A = Ground (to ECU)

This is OBDI style connector S14 SR20DET wiring diagram for Zirconia Heated oxygen sensor;
http://i167.photobucket.com/albums/u159/zilvia_album/SP32-20070926-090420.gif

*
http://i167.photobucket.com/albums/u159/zilvia_album/SP32-20070926-091912.gif