Hi,,,I have a 4cly automatic 03 accord EX...the car won't start.The engine turns over ok..all accessories work ok,but the check eng and batt lights do not work when you turn on the key...so I think that the ecu isn't getting power or it's bad..the fuel pump never runs. So far I.ve checked all the fuses,all are good..no burnt wiring so far...Is there a main relay like on older hondas? anybody have had a problem like this?

 

start buy checking for codes with a scanner if it doesn't communicate with the ECU then its fried and you need a new one. if that's good make sure your immobilizer is reading the transpnder in the key. does the green key symbol on the dash flash when you try to start it.

 

I've tried to scan it,the scanner is being powered by the car,but will not pull any info...says can't link to the car...can a used ecu be installed and work?

If the immobilizer was bad,i think the ck eng light and batt voltage light would still work...?

 

if its not communicating then the ECU is bad. yes a used ECU will work just fine so long as its the exact model for your engine.

 

thanks for the help...I tore out the ecu...lots of corrosion inside of it. I bought a used one ,installed it and towed it down to a Honda dealer for programing...runs now!

 

Hey, glad its all good.

As a preventitive maintenance item another thing you may want to consider at least looking at is the PGMFI relay. Its easy to remove and inspect. It sounds like its working but if you had corrosion in the ECU there is a good possibility this will be affected by the moisture corrosion as well. To be clear if it is you can clean this out. If you go that route I would keep a spare in the glove box as this is a common leave you stuck "no start" causing item.

This may be overkill but I am overly paranoid when it comes to wet electronics.

Adam S.
ASE - Master Technician - A+ Japanese Auto Repair
Honda Specialist
Civic Hatch wtih RSX Motor
Turbo Charged Honda Accord - 2007

 

corrosion on the ecu would leave me to believe the car was flood damaged. were did you get the car from ???. after katrina and the recent flooding on the east coast there must be thousands of flood damaged cars circulating around but there are warning signs to look for.