Ok so my brother has a 2001 civic ex 5 speed. His alternator bolt came loose (I guess this is common on some of the 7th gen civics?) and when it did it fried the ecu since it wasn't grounded properly. We fixed the alternator bolt with a new one and I order a used ecu off ebay for $150. It says its for a 2001 civic ex manual. When I got the original one out the ecu part number read "37820-PLR-A03" and has slots for 3 harnesses. The new one has the number "37220-PLR-A53" and has slots for 4 harnesses. Do I have the wrong ecu? When I look up ecu for our cars, there are definitely over several different ecu part numbers.

 

well yeah there are different ECUs considering some cars where automatic or standerd some were vtec or non vtec.

 

Well, he did mention that both ECU's were from '01 EX manual cars. So, its safe to assume that they're from the same range of ECU's (The PLR octet signifies D17A2).

However, the differences will be in whether they're from a California-specific chassis, or a 49-state chassis. Also, there may be differences for the 4-door versus the 2-door. I'm not sure on that, though.

 

The difference is the version number at the end... A53 denotes an automatic version of the 2001 EX ECU... the A03 that you already had is a manual version.

 

Nationwide salvage listings: Car-Part.com--Used Auto Parts Market

Those are all legit businesses. Be sure to ask if the ECU they have has the exact same number as the one you took out.

 

Weird, 37820-PLR-A03 comes up fine, but 37220-PLR-A53 doesn't even come up in the parts search. Might be Canadian or JDM.

 

I got it on ebay from this used parts store/auto junk yard who is ironically only like 25 minutes away from me. I'm just hoping when I put it in and have it towed to honda to have the key match the ecu so it will start, everything will work fine. When I looked up what the ecu part number is for his car I got a different part number then the one that was in the car to begin with (weird). But Idk the history on this car before we bought it.