Power FC (hopefully) Making the PFC warning light function useful
So, the check engine light does indeed illuminate along with the exh. ovr. heat light by wiring it like you illustrated? So now the issue is getting it to flash when knock and injector duty threshold is exceeded?
There has to be an output line from the PFC. I have noticed that pins 1V, 1P, 2H and 2A all do not have pins on our harness. But on the PFC side the ECU does have pins for those.
Does the JDM harness interface with the EL Unit the same way the US one does to the exhaust overheat light? I guess I wonder do any of the above pins interface with the lights or the el-unit. I would think an unused pin would have to be used to signal the light. The PFC allows you to adjust the frequency of the flashing and that signal I believe would have to come from the PFC somehow in the form of the same flashing frequency. That is why I'm looking for an unused pin.
Do you think you could post some pictures or a pdf of the wiring diagram? That way we could get several people looking at it?
Does the JDM harness interface with the EL Unit the same way the US one does to the exhaust overheat light? I guess I wonder do any of the above pins interface with the lights or the el-unit. I would think an unused pin would have to be used to signal the light. The PFC allows you to adjust the frequency of the flashing and that signal I believe would have to come from the PFC somehow in the form of the same flashing frequency. That is why I'm looking for an unused pin.
Do you think you could post some pictures or a pdf of the wiring diagram? That way we could get several people looking at it?
Thread Starter
Joined: Jan 2002
Posts: 15,622
Likes: 2,725
From: Pensacola, FL
Thread on deciphering the JDM ECU pinouts -
https://www.rx7club.com/power-fc-forum-47/deciphering-jdm-ecu-pinouts-615909/
Dale
https://www.rx7club.com/power-fc-forum-47/deciphering-jdm-ecu-pinouts-615909/
Dale
Thread Starter
Joined: Jan 2002
Posts: 15,622
Likes: 2,725
From: Pensacola, FL
OK, got it working! See the above-referenced thread for more details. Long and short of it - pin 1V is the JDM wire for the overheat warning light. You have to add that wire into your stock harness, as the USDM harness doesn't have a wire at that location. But, it works great - check engine light will blink when you have too much knock or too much duty cycle!
Dale
Dale
Originally Posted by Noxlupus
Dale, you are DA MAN!!! I don't care what HDP says about you! 
Rotary Enthusiast
Joined: Aug 2003
Posts: 959
Likes: 0
From: SC
Originally Posted by HDP
Hey now, you said you wouldn't say anything if I promised not to tell anyone I saw you hugged up with that homeless gay guy...
Rotary Enthusiast
Joined: Aug 2003
Posts: 959
Likes: 0
From: SC
Hey Dale,
I noticed that in your write up here you striped the wires and then soldered the connector. Why not use a Tap-Splice type Connector where there's no need to strip or solder? Just a though.
I noticed that in your write up here you striped the wires and then soldered the connector. Why not use a Tap-Splice type Connector where there's no need to strip or solder? Just a though.
Originally Posted by DaleClark
OK, got it working! See the above-referenced thread for more details. Long and short of it - pin 1V is the JDM wire for the overheat warning light. You have to add that wire into your stock harness, as the USDM harness doesn't have a wire at that location. But, it works great - check engine light will blink when you have too much knock or too much duty cycle!
Dale
Dale
Dale,
Did you confirm that it blinks on knock or injector duty cycle?
Originally Posted by DaleClark
The wire to get the signal to the check engine light is at the ELD computer. Attached is a fun pic I took of the ELD computer - took me a while to find it. It's behind the ECU, up a bit, has a Mitsubishi sticker and a yellow tape wrapped harness going to it. Find the ORANGE/BLACK STRIPE wire - this is the wire to trigger the check engine light.
Dale
Dale
After looking at the FSM, (still unsure which wire is the O/B) it shows this being an output wire from the E/L unit. Shouldn't the O/B wire be removed/disconnected from the E/L unit entirely before connecting it to the 1V pin on the PFC? Would output signal coming from the PFC cause damage to E/L unit?
Thread Starter
Joined: Jan 2002
Posts: 15,622
Likes: 2,725
From: Pensacola, FL
Sorry guys - been busy and haven't peeked in on the thread 
.
It's pin K on the E/L unit. If you go to page B1-B in the wiring diagram, it shows the EL unit and shows the pin order in the connector.
This output wire is basically dead after you remove the stock ECU. I'm not 100% sure if I just tapped into the wire or cut the wire - I'll have to dig around under the dash for that answer. Regardless, it works perfectly in my car, it even turns the Check Engine light on before you start the engine, which will help if you're in an emissions state.
Dale
.It's pin K on the E/L unit. If you go to page B1-B in the wiring diagram, it shows the EL unit and shows the pin order in the connector.
This output wire is basically dead after you remove the stock ECU. I'm not 100% sure if I just tapped into the wire or cut the wire - I'll have to dig around under the dash for that answer. Regardless, it works perfectly in my car, it even turns the Check Engine light on before you start the engine, which will help if you're in an emissions state.
Dale
Originally Posted by DaleClark
Dang, dude! Buy a real shop manual! Call Ray up and get one comin'!
I'll see if I can't take a pic or something of the wiring.
Dale
Call Ray up and get one comin'!I'll see if I can't take a pic or something of the wiring.
Dale
Joined: Nov 2001
Posts: 1,898
Likes: 13
From: Metairie, LA near new orleans
if you look in the WIRING DIAGRAM, located convenitly in the 3rd gen section, you will find section B1-b--and its even in color
!! Some great forum member, cough, scanned it in for everyone. 
!! Some great forum member, cough, scanned it in for everyone.