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Discussion Starter · #1 ·
Does anybody know how to solve this problem I'm having I have a beautiful 2000 honda prelude h22 2.2l the problem I'm having is every time I turn my car off and turn it back on my computer resets itself and doesn't save anything so I can't pass smog
 

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It could be fuses, wiring, ground, or a faulty ECU. Sounds like the ECU's not getting constant power when the ignition is off. Usually it will draw a little bit of power from the battery when off to keep the RAM powered to store data. I'd start by checking fuses and main ground wires (by the battery) and if that's all good I'd check your ECU wiring harness, look for nicks in the wires or a loose connection to the clip. If you can't see anything wrong with the wires look for a ECU wiring diagram look for ATT or BATT or Input Power (IIRC it's 25 and the wire is Yellow and Black) check for power with ignition off.

Let me know if you need anymore help.
 

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Discussion Starter · #5 ·
And I drove for 300 miles and brought it to the smog shop and it still wouldn't pass I checked all the fuses there all good my atts light is on,it has no stero it has a after market alarm system
 

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In the early days to 'defeat' the ECU detuning any timing or fuel changes people would cut the 'always on' ECU power wire. I don't have my Helm's in front of me to give you the exact port but you'd want to check if the ECU side is receiving power. Also check the underhood fuse as you said you don't have a radio installed, though I'm not sure if the car even runs without the radio/ECU fuse in place. Though, at least in my case, the ATTS light will not go on after a fresh reset until you start driving the car, is your ATTS light on immediately when you start the car in the morning? Usually that would be an indicator if it's been reset. Also note that 300 miles might not be enough if there wasn't enough stop/start cycles in the computer, like if you just did a 200 mile drive in one go.
 
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