Kswap ECU + Loom question


Ludo

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Dec 19, 2013
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Hey guys,

I have a DC5 loom for my kswap, just wondering does this mean i have to run the JDM Hondata or would a EP3 UKDM hondata work?

Also is it only a standard pre face DC5 ecu that will work? Or would a facelift DC5 ECU work?

Thanks

Lewis
 
I think you're asking the question in a wrong way.
Are you going to use K-pro? If yes, it doesnt matter if you use a (facelift or not) PRA ukdm or PRC jdm ecu.

The difference with jdm is that the fuelpump doesnt prime via ecu, you'll have to add an additional ground for the fuel pump. Like that your pump will constantly run. (normally your pump will run for a secondor 2/3 when you turn your key, now it will constant run)

If you're going with the PRC ecu and still have to put K-pro on your ecu, i recommend you to ask the guys that do that, to adjust the PRC ecu so that the fuel pump will prime via ecu. I adjusted my JDM prc ecu like that.
 
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I'm using a dc5 loom and a PRA ecu. I had to use the ep3 lambda sensor though to get rid of an engine check light. It couldn't be turned off with the ecu either
 
I'm using a dc5 loom and a PRA ecu. I had to use the ep3 lambda sensor though to get rid of an engine check light. It couldn't be turned off with the ecu either

Thats False, you can get rid of that error.

Make sure u choose the correct options in the closed loop parameter
 
The difference with jdm is that the fuelpump doesnt prime via ecu, you'll have to add an additional ground for the fuel pump. Like that your pump will constantly run. (normally your pump will run for a secondor 2/3 when you turn your key, now it will constant run).

The fuel pump relay is activated by the Ecu same as with a PRA Ecu. The main difference between a PRC and PRA is, the PRC uses a wideband lambda sensor whereas PRA uses a Narrowband lambda sensor.
 
@Ludo you can use the dc5 loom with a PRA Ecu just wire up a narrowband 02 sensor. Obviously the PRA Ecu has a immobiliser so unless your fitting a Kpro to Ecu you will need to bypass the immobiliser.
 
The fuel pump relay is activated by the Ecu same as with a PRA Ecu.

This is also a false statement...The fuel pump WONT work with the JDM PRC ecu, You'll have to ground the fuelpump externally from the ecu to make it work.
The PRA doesnt have this issue...i had both ECU's

But take note:
Do not wire the main relay (E7) or fuel pump (E1) to 12V. This will damage the ECU. Both E1 and E7 are outputs which switch on relays by grounding the ECU output and do not like being forced to eat 12V.
 
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This is also a false statement...The fuel pump WONT work with the JDM PRC ecu, You'll have to ground the fuelpump externally from the ecu to make it work.
The PRA doesnt have this issue...i had both ECU's

But take note:
Do not wire the main relay (E7) or fuel pump (E1) to 12V. This will damage the ECU. Both E1 and E7 are outputs which switch on relays by grounding the ECU output and do not like being forced to eat 12V.

I'm not in the habit of posting information unless I know it is correct and given that I done a K swap DC2 from start to finish including making my own swap loom and used a PRC ecu I know for a fact that the PRC Ecu activates the fuel pump relay.
 
I'm not in the habit of posting information unless I know it is correct and given that I done a K swap DC2 from start to finish including making my own swap loom and used a PRC ecu I know for a fact that the PRC Ecu activates the fuel pump relay.


Maybe i typed it in a wrong way....but i will try to make it clear.

The fuelpump relay will NOT activate on a JDM DC5-R PRC ecu without modifactions! it is a known fact with a K-swap...the only way to make it work is to ground the fuelpump relay. Or make other adjustments to the loom or ecu

here's a quote from Hondata themselves:

Best solution is to modify the PRC ECU to activate the fuel pump on the correct wire which involves pulling it apart and soldering. Another solution is to move the pin in the wiring harness - which will work until you get your other ECU back. Third solution is to ground the fuel pump wire - which might be OK as a temporary fix, but it means the pump is running all the time the key is on.

Look in the K-Pro help menu for the pinout.


Perhaps you modified your loom in the correct way for the fuelpump by accident or something. But it def. wil not work with a stock harnas, i have done the same and other several swaps as you from begin to end and worked out alot of electrical issues. Had different harnasses and ecu's
 
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Going around in circles here. The coil of the fuel pump relay gets it's ground from Ecu to activate, no modification is needed to Ecu just have your wiring correct. If you assumed the wiring was same between PRA and PRC then that was your mistake. The fuel pump pin is in different location. Quite easy to rectify, takes all of 1 minute to swap the pin if your wiring is setup for PRA ecu configuration.
 
The OP is talking about a DC5 loom, assuming it is stock as he didnt state anything about it being modified. The fuel pump wont get its ground from the PRC ecu if he wants to use that one (cirkel). Reading his post i think he is about to buy a Hondata ecu, so the best option would be to let the shop modify the PRC ecu (no big extra costs) so the pump wil work through the ecu WITHOUT modifying anyting to the loom etc.

it doesnt matter wich ecu he chooses as long as he's going with K-pro...He just haves to make note to tell the shop to make modifactions for the fuelpump when going with the PRC ecu. Thats all.

And yes offcourse the relay activates via the ecu like most of the models do.
 
Thats False, you can get rid of that error.

Make sure u choose the correct options in the closed loop parameter


No its not. I used an ep3 engine, dc5 loom and a ep3 k-pro and I had to buy the ep3 narrow band to remove the check light as it wasn't going off through the k-pro.

I was even advised to do this by icetronix in Ireland who have probably done more k-swaps than you have had hot dinners :nice:
 
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