2000 Accord 3.0 blowing ign. coil fuse ?
#1
2000 Accord 3.0 blowing ign. coil fuse ?
My son was working on car and blew ignition coil fuse (15amp) in the left under dash panel. It will turn over but the fuse blows as soon as you turn the key to the ON position. I've check all other fuses and everything is good. For some reason now when I plug up code scanner to data port I get a "NO DATA LINK". The scanner was reading codes fine before the fuse blew. I'm new to the site and have tried everything I know to look for. Can anyone give me some areas to look at.
#2
Power is supplied to data link connector (DLC) from Fuse #3 (15A) in underhood fuse box.
Check Pin 16 of DLC for 12V. If missing, there is a problem w/ power supply to DLC. Lower RH side (narrow row) of DLC looking at DLC. Wire connection is wht/grn.
Fuse 3 in underdash box is 7.5A accessory fuse. Fuse 1 is 15A Main Fuel Relay power supply fuse. It could be a wiring fault or defective fuel pump (shorted). Some testing to confirm source of short is indicated.
good luck
Check Pin 16 of DLC for 12V. If missing, there is a problem w/ power supply to DLC. Lower RH side (narrow row) of DLC looking at DLC. Wire connection is wht/grn.
Fuse 3 in underdash box is 7.5A accessory fuse. Fuse 1 is 15A Main Fuel Relay power supply fuse. It could be a wiring fault or defective fuel pump (shorted). Some testing to confirm source of short is indicated.
good luck
#3
Circuit D46.docx
Talking further with my son, he applied 12V constant to the blue/yellow wire leaving the EGR valve to keep the CEL from coming on and giving a error code (P0401). Something he read on the net.
I've unplugged all harnesses from each item in the attached D46 circuit and it still blows the #11 15 amp Ignition circuit fuse which leads me to believe there is something else in this circuit that I'm not finding or a frayed/burnt wire causing the short.
I'm I missing something? I've visually inspected all other fuses and they are good. Is there a main ignition relay under the dash that may be somehow connected to this circuit?
Talking further with my son, he applied 12V constant to the blue/yellow wire leaving the EGR valve to keep the CEL from coming on and giving a error code (P0401). Something he read on the net.
I've unplugged all harnesses from each item in the attached D46 circuit and it still blows the #11 15 amp Ignition circuit fuse which leads me to believe there is something else in this circuit that I'm not finding or a frayed/burnt wire causing the short.
I'm I missing something? I've visually inspected all other fuses and they are good. Is there a main ignition relay under the dash that may be somehow connected to this circuit?
#4
Fuse 11 (15A) supplies power to the ignition coils and nothing else. It seems more likely that one of the coils has a shorted condition.
Since fuse blows immediately, you may be able to test by disconnecting all coils and sequentially connecting them w/ keyswitch On. When fuse blows, you've just connected the faulty coil.
Your son connected 12V to a voltage reference line from PCM, normally 5V. I don't know if this caused damage or not, but it's possible.
good luck
Since fuse blows immediately, you may be able to test by disconnecting all coils and sequentially connecting them w/ keyswitch On. When fuse blows, you've just connected the faulty coil.
Your son connected 12V to a voltage reference line from PCM, normally 5V. I don't know if this caused damage or not, but it's possible.
good luck
#5
Thanks for the great help. Thats a start and I'll do this coil test and hopefully find the fault. I've got the complete wiring diagram and I've been looking at it from the point of where the 12V was applied to the BL/YL wire at the EGR valve and following the path. It would have traveled through several sensors and ending up at the #11 fuse from what I can see. I will post back with the coil test results.
#7
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#10
Thanks for all of your help.
Last edited by stroker393; 01-24-2016 at 02:44 PM.