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Discussion Starter · #1 ·
Im having o2 issues? I replaced still getting code 0032, so then I started with the volt meter. Im getting battery voltage (which if I understand should be milivoltes)
to white wire on o2 side, solid black on bike side, heater ground . Ive tried to look wire loom over and not seeing any damage. Anybody have any ideas???,,
 

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Im having o2 issues? I replaced still getting code 0032, so then I started with the volt meter. Im getting battery voltage (which if I understand should be milivoltes)
to white wire on o2 side, solid black on bike side, heater ground . Ive tried to look wire loom over and not seeing any damage. Anybody have any ideas???,,
Heater voltage should be battery voltage so likely you are probing the wrong wires. This should explain and help test the heater voltage, bias and signal checks . Kinda crude vid but good enough. Ignore the fact it's a Muscle as they are all the same with the 12mm sensors.
Ron
 

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That video is where I got my info. I check and double checked wires and voltage. Where im getting battery voltage is the heater ground wire. 😡 I've cut insulation to check for any breaks. Nothing the only thing I can think to do is ecm? But I am getting battery voltage to 02 sensor heater ground??
 

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That video is where I got my info. I check and double checked wires and voltage. Where im getting battery voltage is the heater ground wire. 😡 I've cut insulation to check for any breaks. Nothing the only thing I can think to do is ecm? But I am getting battery voltage to 02 sensor heater ground??
Bat voltage comes from system relay for both and both sensors share a common ground to pin 3 at the ECM. Harness it's yellow/green for bat+ from relay and brown/black to ECM . On the sensor side of plug it's violet and white for the heater circuit. Logically if the rear isn't throwing the same code, the common grounding at the ECM should rule out an ECM.
Ron
 

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Ron-
Voltage on the ground side of a circuit would indicate an open ground. The voltage has no place to go, therefore will still be available after the load. Is the heater control duty cycled or just on/off?
 

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Ron-
Voltage on the ground side of a circuit would indicate an open ground. The voltage has no place to go, therefore will still be available after the load. Is the heater control duty cycled or just on/off?
I think it's on full time but don't know for sure. It wouldn't make sense to switch it as there's a time delay for heat. Yes voltage present on ground until ecm closes it. Then the heater warms up.
Ron
 

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Yeh mines tool old to be running O2’s or I would test it. But it’s common in the automotive industry to duty cycle the heater (ground side control) to control current flow. That shows up as voltage on the ground side when measured with a DVOM although lower than charging voltage. If he has charging system voltage on ground it would lead me to believe there’s no ground being supplied.
 

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Yeh mines tool old to be running O2’s or I would test it. But it’s common in the automotive industry to duty cycle the heater (ground side control) to control current flow. That shows up as voltage on the ground side when measured with a DVOM although lower than charging voltage. If he has charging system voltage on ground it would lead me to believe there’s no ground being supplied.
Except in this case front and rear share the same ground source of terminal 3 of the ECM. Rear is not throwing a code so this could be an open ground wire between the ECM and the front sensor, as I see it. As for switching, it's possible. Once up and running the heater isn't really needed. It's only to light them up quicker on start up and possibly for idle conditions where the EGT is lower. I'd think on the EOEO situation they would remain active for heating?
Ron
 
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