84SE Oscillator Relay - FOUND!
#1
84SE-EGI helpy-helperton
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84SE Oscillator Relay - FOUND!
For those interested in this part, it is mounted behind the driver's side headlight bucket and looks like a relay over in front of the battery box. It's between the battery box and the headlight assembly, and has 4 wires going into it, with a separate black ground, with it's own connector.
Anyway - reading through the wiring diagram in my manuals, it appears to work with the computer to pass information about water temperature, air temperature and other details, so I think it's important enough to change.
My old one was heavily corroded from battery acid probably splashing onto the connector. Found one at a local Mazda dealer for $56 and they have to special order it for me - should be around a week before it arrives.
Currently, the car seems to run fine without it, but thought I'd give a before and after to help you guys determine if it's truly needed. HTH,
Anyway - reading through the wiring diagram in my manuals, it appears to work with the computer to pass information about water temperature, air temperature and other details, so I think it's important enough to change.
My old one was heavily corroded from battery acid probably splashing onto the connector. Found one at a local Mazda dealer for $56 and they have to special order it for me - should be around a week before it arrives.
Currently, the car seems to run fine without it, but thought I'd give a before and after to help you guys determine if it's truly needed. HTH,
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Re: 84SE Oscillator Relay - FOUND!
Originally posted by LongDuck
Anyway - reading through the wiring diagram in my manuals, it appears to work with the computer to pass information about water temperature, air temperature and other details, so I think it's important enough to change.
Anyway - reading through the wiring diagram in my manuals, it appears to work with the computer to pass information about water temperature, air temperature and other details, so I think it's important enough to change.
I'm afraid I would have to disagree.
The oscillator is simply a circuit that converts the battery 12v DC to a pulse to drive the buzzer at a certain frequency. It operates the buzzer for low oil and low coolant conditions, as jerij mentioned. It has nothing to do with water, temperature or other sensors or signals.
It does have a terminal in common with the CPU (which only controls such mundane tasks as the Ign key reminder buzzer and timing for the wiper motor and washer functions), but that is so the CPU can also sound the dash buzzer with it's own, built-in oscillator. It has nothing to do with the EFI, which is controlled by the E.G.I. and Emissions Control Unit (ECU).
The oscillator's 12v supply comes from the Choke and Check relay. If the alternator fails, the relay would cut power to the 12A choke solenoid and the oscillator (why they bothered, I don't know), while lighting the dash warning light; but otherwise it has nothing to do with the choke(12A) or fast idle(13B).
If the oscillator fails or is removed, the only difference is that the low oil and low coolant buzzer will not sound. (On a side note, I have no idea why they located it where they did; I would have expected it to be under the dash.
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I could scan the relevant areas of the factory wiring diagram, if you would like.
Just a friendly FYI.
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-John.
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84SE-EGI helpy-helperton
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Thanks for the update - money's already spent at the dealer, so I'll just wait for it to show up. At least I'm getting closer to 'factory' build...
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Originally posted by LongDuck
- money's already spent at the dealer, so I'll just wait for it to show up.
- money's already spent at the dealer, so I'll just wait for it to show up.
(Unless you were to rig a bulb to the sensors, but I'd go with the original equipment, as you have.)
$56.00 is cheap insurance, I'd say.
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