im hardwiring a bosch universal into the obd1 side of a conversion harness. does it matter where on the ecu each black goes. i know the white goes to d14, and the green goes to a6. the other places for the heater controls are like a25, and one more that i have written down in the garage. so my question again, do i have to put each black wire to a specific spot in the ecu (say wire in the 3rd spot on the harness goes to a25)? or can i just hook them up either way ?

 

they are both heaters, so i guess splice the two blacks into the single heater you have.

 

hmmm... the 2 spots on the ecu where the blacks would go; one is a ground and the other is positive, so i just dont want to wind up crossing them and have to go back and re-solder

 

well double check, thought the 3 wire grounded through its body to exhaust.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rtype11 &raquo;</TD></TR><TR><TD CLASS="quote">well double check, thought the 3 wire grounded through its body to exhaust.</TD></TR></TABLE>

im sorry man, now i real confused. this sensor is a 4 wire. i gotta stop doing so much schoolwork so i can focus on more important things like understanding how to wire up o2 sensors...

 

Didn't the Bosch sensor come with any paperwork that says which wire is what?

I thought the 2 same-color wires (black) are the heater. They should measure 10 to 40 ohms between them & no continuity to ground. One of them gets power from the main relay, I guess that's also connected to A25; that's battery voltage, not control 'from' the ECU. The other heater lead goes to A6. I don't know about green to A6, so maybe green is actually one of the heater wires??

When the senor is cold, the signal wire should look like an open circuit; no continuity to anything. I don't know whether the ground side of the sensor is ALSO connected to ground? If not, it'll also measure open. Check all the wires out with an ohm-meter & let us know what they measure...