Car is a 1991 Euro spec car with KEjet. I am reinstalling the exhaust on the car. I have some TR wiring diagrams, but none seem complete for my late example TR. The wiring harness which connects the oxygen sensors to the car uses two amp connectors. One white, one black. There are also two single wires with spade connectors. One black, one green. My notes show the black amp connector connects to the o2 sensor for 7-12. The white for 1-6. Does it matter which o2 sensor / bank 0f cylinders the single wires go to? Do the single wires feed the signal, or are they used to feed power or heat the o2 sensors?
??? I don't understand your question but in general O2 sensor wiring looks like this over the development of the O2 sensor. Image Unavailable, Please Login
Picture is worth a thousand words. I believe the big 2 wire AMP type connector plugs into one or the other connector in the wiring harness, depending on which bank the sensor is measuring. The single wire is the question. What does it do and does it matter which of the two available single wires in plugs into?
The two pin connectors are just a +12V and ground for the internal heater of the O2 sensor = doesn't matter who is connected to who. The single spade connector is the signal output from the O2 sensor = it is hugely important that each one is connected to the correct injection ECU: The single wire from the O2 sensor mounted in the 7-12 exhaust stream needs to connect to pin 8 of the forwardmost injection ECU (which runs the EHA for the 7-12 bank). The single wire from the O2 sensor mounted in the 1-6 exhaust stream needs to connect to pin 8 of the rearmost injection ECU (which runs the EHA for the 1-6 bank).
Thanks. I am going to print your response and add it to the manual. All the KE supplement to the manual says is that the 7-12 plug connector (single wire) is black. On my car both single spade connector wire plugs are identical, but the individual wires are green or black.
If connected backwards one bank goes full lean and one bank goes full rich. Lots of catalytic converters met their end that way.
Yes, the boots on the single wires of the original Ferrari-specified TR Bosch O2 sensors were color-coded black and white (and also probably had different wire lengths), but the replacement Bosch O2 sensors are now just black = yours have been replaced at some point in time. And there was a black marker strap on one of the harness side single spade male connectors. Here's a shot of an original TR O2 sensor connectors situation showing one white boot and one black boot on the single wires (not mine, and the extra blue markings/labels are something someone added -- ignore the note about the ground strap). Image Unavailable, Please Login However, I wouldn't trust anything about "colors", and would use a multimeter (ohmmeter) to confirm the connections that I listed in post #4.
I´m late with answering and steve already said it: this AMP connector is only for 12V plus and minus for heating the sensor and the 1 wire with the big rubber cap is for signal from the sensor. former with only 1 wire each sensor those wire for signals from the sensors had always those big rubber caps.
Odd that the AMP connectors are different; if they only feed power for heating, why bother. The rubber caps have long degraded on mine and disappeared, they are only two loose wires with spade connectors now. Once connected, I insulate them with heat shrink tubing and secure them. My TR had hollowed out cats when I got it, it has run test pipes since 2008 and always passed emissions testing. As it is about to leave the UAE for good and go back to Italy (it was actually sold new there) I need to install a pair of NOS catalytic converters I put on the shelf years ago to pass the initial inspection. Thanks for clarifying and likely preventing the destruction of the new parts.
None on the plug, the ecu is buried inside the fender. I played around with an ohmmeter, so think I figured it out.
The schematic on page 74 of the US TR OMs in Section 3 shows the injection ECU connector pin assignments, and they are also shown on the schematic on page D106 of the TR WSM Supplement.
Found it on pg. D106. Thanks. Next comes the shifter alignment. It slipped out of 2nd. Ugh. I guess you put it back in 2nd, then align the shifter?
