16v Mini Club Forums  

Go Back   16v Mini Club Forums > General Public Area > Honda Chat

Reply
 
Thread Tools Display Modes
Old 24-01-2010, 07:00 PM   #1
ozy1410
Senior Member
 
Join Date: Jun 2009
Location: Scotland
Posts: 147
Default Main relay

Hi can anyone tell me where these wires go on the main relay? I know there is quite a bit mentioned on this forum but i think most of it is for 1.6 vtec. I'm using the loom out a 98 1.8 civic and the colours seem to be a different.

Pin 1 Yellow/white
Pin 2 Black
pin 3 Yellow/Black
Pin 4 Not used
Pin 5 Black/red
Pin 6 Black/white
pin 7 Yellow/green
Pin 8 Green/yellow

Any help would be great.
ozy1410 is offline   Reply With Quote
Old 24-01-2010, 07:43 PM   #2
strudel
Senior Member
 
strudel's Avatar
 
Join Date: Oct 2003
Location: Edmonton,AB Canada
Posts: 1,425
Default

You will require the PGMFI schematic from the service manual to see exactly where they belong and colour coding. If you can't get it online then go to the nearest Honda dealer and see if they will print one out for you from their electronic manuals.

You could look at this one but no colour coding but does show where they go. It unfortunately doesn't provide the plug pinout orientation. Normally there are only 7 wires used in an 8 pin plug. You will have to figure out the blank spot. Wire colours are not always the same from year to year but the Main Relays are all similar and most likely interchangeable. JS

http://www.taktik.co.nz/mini1/misc/m...ingdiagram.pdf
__________________
Austin Mini Van with DOHC Honda HP
http://www.angelfire.com/droid/strudel
Honda reliability and power combined with Mini cachet and style.
strudel is offline   Reply With Quote
Old 25-01-2010, 03:58 AM   #3
Freebies
Senior Member
 
Freebies's Avatar
 
Join Date: Apr 2009
Location: Montreal, QC, Canada
Posts: 1,372
Subframe: MTB
CC: D15B
Make: Honda
ECU: MTD Frame, not MTB
Default

Check Wannago wiring diagram... All pins are shown with a small diagram. Take the unused pin in reference to determine all others. This diagram is the best one i ever seen so far.

I like the use of the relay to activate the V-tec solenoid. This means a switch or an rpm comparator can be used to activated the Vtec solenoid at different time then current honda ECU determines...
Freebies is offline   Reply With Quote
Old 25-01-2010, 05:10 AM   #4
strudel
Senior Member
 
strudel's Avatar
 
Join Date: Oct 2003
Location: Edmonton,AB Canada
Posts: 1,425
Default

Fereebies,

Your a gem. I didn't see it in the little yellow box with the arrow pointing right at the main relay. I guess this saying is correct after all. Can't see the forest for the trees! JS
__________________
Austin Mini Van with DOHC Honda HP
http://www.angelfire.com/droid/strudel
Honda reliability and power combined with Mini cachet and style.
strudel is offline   Reply With Quote
Old 25-01-2010, 03:25 PM   #5
ozy1410
Senior Member
 
Join Date: Jun 2009
Location: Scotland
Posts: 147
Unhappy Update

Hi guys. Had another go at it today but still not really better off. Although the wire colours and termninals seem to be different on the main relay from most diagrams i'm pretty confident i've got it wired up right. As it stands when i turn the ignition on i get one click from the relay and power out of it to the ECU for the injectors, the problem seems to be the switched earth from the ECU to the fuel pump and i'm sure it's an immobiliser problem. Apparently the red wire from the immobiliser is meant to go to the ECU but i can't see where!! Do any off you know? On the immobiliser box i have connected the

Yellow/white- Bat 12v
Yellow/black -ign 12v
Black- Neg
Pink - Dash
Black/green Starter switch? (not sure if correct)
Red- ECU? what terminal??????
Green/red Not got a clue!!

Through this wiring process it seems in my case yellow and white is bat live, Yellow/black is ign live and black is earth witch makes me think i have the main relay wired up correct if this makes any sense!!! Please help

Also i have a wire from the ecu not connected it is Service check signal,brown and comes from D4. Do you know what is for and where it connects?? Cheers

Last edited by ozy1410; 25-01-2010 at 03:28 PM.
ozy1410 is offline   Reply With Quote
Old 29-01-2010, 08:54 AM   #6
WanaGo
Senior Member
 
WanaGo's Avatar
 
Join Date: Nov 2006
Location: Wellington, New Zealand
Posts: 1,138
Subframe: Home Made
CC: 1600
Make: Honda
ECU: P30 - Chipped with Crome Gold
Default

Ozy, have a look at my diagram, it shows exactly what pins on the ECU and what pins on the main relay....

Your statement concerns me however...

Quote:
As it stands when i turn the ignition on i get one click from the relay and power out of it to the ECU for the injectors
When you turn the ignition on, your fuel pump should prime - it shouldnt do anything with the injectors at this stage.

Quote:
the problem seems to be the switched earth from the ECU to the fuel pump
Switched earth from the ECU to the fuel pump? The ECU isnt directly connected to the fuel pump, it is via the Main Relay... and it doesnt switch earth anyway... its 12V.

You may already have your issues sorted out as I just saw this is a few days old now.

WanaGo
James
__________________
B16A2 Vtec Mini with custom subframe - On Road. My Mini Gallery. Here is my wiring Diagram - My Wiring Diagram. Here is my labelled Engine Loom - pre-Chop Engine Loom Picture
WanaGo is offline   Reply With Quote
Old 29-01-2010, 06:00 PM   #7
ozy1410
Senior Member
 
Join Date: Jun 2009
Location: Scotland
Posts: 147
Default

Hi and thanks for the reply. i've just read back what i jotted down and your right....i could of explained my problems a bit better. Basicaly when i turn on the ignition i hear the main relay click once. I get power out supplying the ECU but don't seem to be getting the earth which activates the fuel pump relay. The car starts and runs properly when i run a live wire to the fuel pump which makes me think it is an immobiliser problem. Unfortunatly the pins on my main relay are different from the ones on your diagram.
ozy1410 is offline   Reply With Quote
Old 29-01-2010, 06:02 PM   #8
ozy1410
Senior Member
 
Join Date: Jun 2009
Location: Scotland
Posts: 147
Default

Well done on the diagram anyway. Well impressive. Bet that took a few hours!!
ozy1410 is offline   Reply With Quote
Old 29-01-2010, 09:02 PM   #9
WanaGo
Senior Member
 
WanaGo's Avatar
 
Join Date: Nov 2006
Location: Wellington, New Zealand
Posts: 1,138
Subframe: Home Made
CC: 1600
Make: Honda
ECU: P30 - Chipped with Crome Gold
Default

Hey
Cool as - but still I am a little unsure with what you said....

Quote:
I get power out supplying the ECU but don't seem to be getting the earth which activates the fuel pump relay
Correct the Main Relay supplies the ECU with power, however it doesnt 'give' the fuel pump relay an earth.... The Main Relay only supplies +12V to things, it doesnt supply any earths...

The fuel pump relay is supplied power from the Main Relay via pin 4 of the Main Relay (if you refer to my diagram). This is 12V... The other side of the fuel pump relay is GND, which isnt switched.

As I say, the main relay only supplies power - it doesnt supply any earths.

This may help - its what I wrote on Carl V's honda build... it may help you... may not either... :P


To understand the PGMFI relay (if you are interested) its quite simple. Have a look at my wiring diagram, just for reference - link at the bottom of my posts in my sig.
The PGMFI relay is quite simple when you look at it.
-Constant power enters Pin 7, but is stopped by the first relay.
-When you turn the ignition to ON, Pin 5 receives power, which is the coil for Pin 7, ie power from Pin 7 now gets through the first relay. This powers B1 and A25 of the ECU, which is the ECU power. It also powers the 2nd relays coil, grounded by the ECU on Pin A7.
-When that happens, relay 2 allows the switched (Ingition ON) power from Pin 5 to flow out of Pin 4, which goes to your fuel pump, to prime.
-After a set time (not pressure as far as I am aware) the ECU disconnects GND from ECU pin A7, which stops relay 2, so the fuel pump stops priming.

-When the key is switched to START to crank the starter motor, power flows into Pin 2 of the PGMFI relay, again switching relay 2, and providing the Fuel Pump with power again.
-The START signal also goes to ECU pin B9 which tells the ECU that you are cranking the engine, and to run that part of the ECU code accordingly.
__________________
B16A2 Vtec Mini with custom subframe - On Road. My Mini Gallery. Here is my wiring Diagram - My Wiring Diagram. Here is my labelled Engine Loom - pre-Chop Engine Loom Picture
WanaGo is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 11:11 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.