ok so my buddy has a 96 civic dx. he just swapped his tranny and **** and changed it to manual from automatic. he's still running the automatic ecu and he throws a check engine light and his reverse lights don't work. he went to go and change the ecu to another P2E from a civic hatch, but it didn't fit. my friends p2e has 4 plugs and the ecu he got only had 3. i'm curious if there are variations between the p2e's or what. he just wants to get the manual dx ecu and i'm wondering if his harness is different because it's auto?

 

Since your buddy has a 97 Dx, he needs an ECU from that generation (96-98). From what year hatch did he source the other P2E? The 4th ECU plug is for the automatic tranny. 5-spd ECUs only have 3 connectors.

 

he told me the ecu was from the same year civic as his, but the only difference was it was a hatchback and not a sedan. we were able to plug in all 3 plugs into the ecu leaving the 4th one out, but then the car wouldn't start.

 

How sure are you that the sedan P2E is actually good?

Is the motor turning over at all? Does it act like it might catch, but doesn't? Any CEL's?

 

All 96-00 ecu's have only 3 plugs. The 4th spot on the ecu has no pins to plug anything into. Like mentioned above, you will neeed a 96-98 obd2a ecu. You cannot use a 99-00 ecu if that is what you currently have.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wadup &raquo;</TD></TR><TR><TD CLASS="quote">All 96-00 ecu's have only 3 plugs. The 4th spot on the ecu has no pins to plug anything into. Like mentioned above, you will neeed a 96-98 obd2a ecu. You cannot use a 99-00 ecu if that is what you currently have.</TD></TR></TABLE>

You're a hair incorrect sir.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EE_Chris &raquo;</TD></TR><TR><TD CLASS="quote">The 4th ECU plug is for the automatic tranny. 5-spd ECUs only have 3 connectors.</TD></TR></TABLE>

 

bah, i was going by this: http://www.hondata.com/techecuid.html

damn hondata for confusing me

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EE_Chris &raquo;</TD></TR><TR><TD CLASS="quote">How sure are you that the sedan P2E is actually good?

Is the motor turning over at all? Does it act like it might catch, but doesn't? Any CEL's?</TD></TR></TABLE>

it's a hatch ecu going into a sedan.. but the ecu was working while it was in the hatch. when the hatchbacks p2e is plugged into the sedan the engine doesn't even crank at all.

 

Its not the ECUs fault if the starter isn't turning the motor over. When you had the auto shifter in neutral or park, it provided a path for voltage to get to the starter. Now that you've removed it, what took its place?

With a stock 5-spd setup, there is a clutch switch that energizes a relay. The relay then provides a path for voltage to get to the starter (from the ignition switch).

Did you install the relay and switch? If yes, time for a meter - you need to see where voltage is getting cut off from getting to the starter.

 

when he uses the auto ecu it starts and drives perfectly fine, but it throws a code because the ecu is for a auto.

 

is there something else he needs to do to the engine or tranny when switching from auto to manual other than just swapping the tranny, pedal assembly, shift linkage, and ecu?