HELP! GSR ECU Hardwiring Obd2 shell obd1 engine

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GsR_CiViC

New Member
Here's the deal gentlemen! I've been reading these forums for a little over 3 years and all info was very helpful.
I Havn't been able to locate this info on the forums so maybe you guys can help.

-I have a 1996 Gsr that was stolen last year and completely stripped (lowering shocks and all).:(
-I Just bought an obd1 b18c1, obd1 ECU (p72)

-Heres the thing: The ecu connectors were cut (they stole them too).... I bought the obd1 connectors to plug right up to the ecu, So now i have to hardwire them in.
a few of the wires match (completely) but more than half are questionable¿:confused:

-The b18c1 did not come with an engine harness or dizzy, but i have an obd2 LS harness in storage.:D

Can i use this harness being that my shock tower plugs should match and swap injector plugs and add VTEC?:rolleyes:

- what other modifications would be needed?

-which DiZ-NiZzY should i use?

I'm trying to get everything ready to do this (new head - gasket, water pump, timing, etc...) and i want to tackle the electrical first.

Any suggestions are greatly appreciated!!!!
 
if your going obd1 you need a gsr obd1 distributor and change the plugs on the harness.
here is the obd2 wiring diagram tells ya the wire colors
plugs.jpg



obd2a.pin.schematics.gif


and here is the obd1 colors and functions
A1-INJ1 INJECTOR#1 Brown, Battery Voltage with KOEO
A2-INJ4 INJECTOR#4 Yellow, Battery Voltage with KOEO
A3-INJ2 INJECTOR#2 Red, Battery Voltage with KOEO
A4-VTS VTEC solenoid GRN/YEL, n/a
A5-INJ3 INJECTOR#3 Blue, Battery Voltage with KOEO
A6-PO2SHTC O2 sensor heating element Org/Wht, Battery Voltage with KOEO
A7-FLR1 fuel pump Grn/BLK, Battery Voltage with KOEO
A8-empty A7 and A8 have the same circurt, so they can be the same
A9-IACV IAC valve Blk/Blu, About 10v KOEO on Warm engine
A10-empty
A11-EGR Control Solenoid Valve (if the ECU has it) Red, n/a
A12-FANC engine coolant temp switch Blu/red, n/a
A13-MIL MIL (check engine light) Blu/wht, n/a
A14-empty
A15-ACC (a/c compressor clutch) Red/Blu, n/a
A16-ALT C alternator Wht/Grn, n/a
A17-IAB IAB Solenoid Pink, n/a
A18-Org/Red, Transmission Control Module (A/T), n/a
A19-White, Intake control solenoid, Battery Voltage with KOEO
A20-PCS EVAP purge control solenoid Red/Grn, n/a
A21-ICM Yel/Grn, Ignition Control Module output signal, About 10V KOEO
A22-Igniter, same as A21
A23-PG1 ground Black, Power ground, less than 1V
A24-PG2 ground same as A23
A25-IGP2 to main relay and to ground Yel/blk, Battery positive from Main relay, Battery Voltage with KOEO
A26-LG1 gound Blk/red, less than 1V

B1-IGP2 to pin A25 Yel/Blk, Battery positive from Main relay, Battery Voltage with KOEO
B2-LG2 ground to shields for CYP & TDC Brown/Blk, <1V
B3-Orange, upshift/downshift comparative input, n/a
B4-Pink, upshift/downshift comparative input, n/a
B5-ACS a/c switch Blu/Blk, a/c input, ~5V with KOEO & A/C off; <1V KOER with A/C & blower on
B6-empty
B7-Light green, Park/Neutral switch (A/T), <1V in Park or Neutral with KOEO; 5V in Park or neutral with KOER; Battery voltage in all other positions
B8-PSPSW PSP switch Red/Green, Power steering oil pressure switch, 0V KOEO; Battery Voltage KOER While slowly turning steering wheel
B9-STARTER SIGNAL starter signal Blue/red, Battery Voltage in the START position (clutch depressed on M/T models)
B10-VSS vehicle speed sensor Orange, Pulses 0-12V while turning the left front wheel
B11-CYP P CYP(#1 piston position) -P Orange, CYP sensor input, n/a
B12-CYP M CYP -M White, CYP sensor signal, n/a
B13-TDC P TDC(top dead ceter) -P Org/Blue, TDC sensor input, n/a
B14-TDC M TDC -M Wht/Blue, TDC sensor signal, n/a
B15-CKP P CKP(crank position) -P Blu/Green, CKP Sensor input, n/a
B16-CKP M CKP -M Blu/yel, CKP Sensor signal, n/a

D1-VBU Back Up Power Wht/Yel, Battery positive From battery through Fuse Box, Battery Voltage at ALL times
D2-BKSW brake switch Grn/wht, Battery voltage at all times
D3-KS Knock Sensor Red/Blue, n/a
D4-SCS service check connector Brown/Wht, ~5V (M/T); ~11V (A/T)
D5-empty
D6-VTM VTEC pressure switch Light Blue, n/a
D7-TXD/RXD (data link connector) Light Green/Red, n/a
D8-empty
D9-ALT F alternator Wht/Red, Alternator Charging Signal, ~4.5V KOEO; Decreases under Electrical load (Headlights & rear defogger on) At warm idle
D10-ELD electric load detector input Grn/Blk, n/a
D11-TPS (throttle position sensor) Signal Red/Blk, ~0.5V KOEO with throttle fully closed; ~4.5V KOEO with throttle fully open
D12-Wht/Blk, EGR Valve Lift sensor, ~1.2V KOEO
D13-ECT (engine coolant temp) sensor input Yel/Blu, ~5V KOEO (varies with temperature)
D14-PHO2S O2 sensor White, heated 02 sensor Signal, 0.4-0.5V when ignition is turned on; drops to less than 0.1V within 2 minutes
D15-IAT Intake Air Temperature sensor signal Red/Yel, .05-4.5V KOEO(Varies with temperature)
D16-VREF (no info)
D17-MAP Map Signal Wht/Blu, ~3V KOEO (Varies with Temperature)
D18-Light Green/Blk, Transmission Control Module (A/T Only), n/a
D19-Red/Wht, Reference Voltage, ~5V KOEO
D20-Yel/Wht, Reference Voltage, ~5V KOEO
D21-Blue/Wht, Sensor ground, <1V
D22-Green/Wht, Sensor ground, <1V

obd1%20ecu%20plugs.gif


that might help ya
 
That is exactly what i needed. i'm gettng started tomorrow!
-I'm hoping i can trace the wires coming from under the dash to thier respected locations (the ones that are exact same color)?
-any suggestions for them?

THANKS
 
Okay,...
Seems that my obd1 plug wires are different colors than you say above....
 
So your repinning up the obd1 ecu plugs with an obd2a wireharness? Let me figure out how to ask this, the wires your "matching these up with" Were they in the car originally or did you get it with the new engine? Why not just buy a new wire harness?
 
Last edited:
Pooptugboat, because buying a new harness costs money :p DIY feels better. lol

Think you could go down the list and name off what's not matching up? Or what has matched up so far? You know what you can always do if your unsure is whip out the multimeter and check for continuity between the connector pin in the engine bay and the end of the wire by the ecu.

Just let me know what color wires or what systems' wires are left to be connected, or have already been connected.
 
Got a deal on the engine with 120K (did not come with harness or dizzy).. So here's the deal
I work two jobs, So i get to the shop every now and then to Do it so right now im cleaning the interior out and just put new head gasket on the motor, water, pump etc.. (Walls look good!) already compression tested. I sill have to put the cams back in etc Because i want to clean the outside of it to "like new" as well as the block.
I have both helms manuals for obd1 and obd2 teggys AS well as a haynes for 94-00

YBLEGAL - I'm on my way out to work now, i have a list of what started to not match up, it became so many that i went to sleep without finishing with much upsetment <--if thats a word :)

ill be back a lil later and ill throw it up!.. i know on a plug the injectors were the same
 
So Far....

"and here is the obd1 colors and functions
A1-INJ1 INJECTOR#1 Brown, Battery Voltage with KOEO
A2-INJ4 INJECTOR#4 Yellow, Battery Voltage with KOEO
A3-INJ2 INJECTOR#2 Red, Battery Voltage with KOEO
A4-VTS VTEC solenoid GRN/YEL, n/a
A5-INJ3 INJECTOR#3 Blue, Battery Voltage with KOEO
A6-PO2SHTC O2 sensor heating element Org/Wht, Battery Voltage with KOEO
A7-FLR1 fuel pump Grn/BLK, Battery Voltage with KOEO
A8-empty A7 and A8 have the same circurt, so they can be the same
A9-IACV IAC valve Blk/Blu, About 10v KOEO on Warm engine
A10-empty
A11-EGR Control Solenoid Valve (if the ECU has it) Red, n/a
A12-FANC engine coolant temp switch Blu/red, n/a
A13-MIL MIL (check engine light) Blu/wht, n/a
A14-empty
A15-ACC (a/c compressor clutch) Red/Blu, n/a
A16-ALT C alternator Wht/Grn, n/a
A17-IAB IAB Solenoid Pink, n/a
A18-Org/Red, Transmission Control Module (A/T), n/a
A19-White, Intake control solenoid, Battery Voltage with KOEO
A20-PCS EVAP purge control solenoid Red/Grn, n/a
A21-ICM Yel/Grn, Ignition Control Module output signal, About 10V KOEO
A22-Igniter, same as A21 (contn'd) "

HERES WHAT I GOT...SO FAR ANYWAY.... ON MY OBD1 PLUGS.....

A-1,2,3,4 are same...
a5 - Baby bLue
a6 - Orange/black stripe
a7 - green/yellow stripe
a8 - same as a/7 supposedly but NOT THERE
a9 - Green/white striZzZipE
a10 - EmpTiZzZy (empty:D)
a11 - green/orange stripe
a12 - yellow/green stripe
a13 - green/orange stripe
a14 - Empty
a15 - black with red stripe

THis is all i got to before the sense of worthlesness kicked in. I then took the plugs back to the shop. I wanted to get my notes and diagrams all together and Correct before i whip out that multimeter^_^ I'm still even unsure of what the pins REALLY are but thats what i have the manuals for.. im trying to get the colors to their respective locations on the plug so i know what they are.

*I dd notice while doing this that one of the pins that were empty I think was for VTEC ... Could this mean i have the obd1 NON VTEC PLUGS??

I'll post some pics as soon as i find out how to send them from my phone to email (my phone doesn't have the underscore_)
 
Correction!

A4 - I'm pretty sure is EMPTY... i will confirm tomorrow night SORRY!
a5-- and on is accurate..
 
*update*
I just took the dashboard and ac/heater boxes out to expose all wires... i did not have this color chart above with me due to neglect. But heres the thing...
-This was my first attempt to even see what i working with. I started off by Plugging in my engine harness to my shock towers. I then took a battery and grounded it to my chassis, after that I wired up a pin to the positive (on the batt).. I had a buddy of mine ground the multimeter, and hold the hot side on one of the wires.. then i went to the engine bay with my "super plug invention" and probed every plug in the harness to try and get a signal...thing is the multimeter is sensitive and i was getting some haywire numbers on multiple wires???

So then I Connected my some of my obd1 plug(wires) to my obd2 chassis wires (the colors that matched up) But there are twins of some colors.. and i dont even know if this is right (even if the wires match)...
I plan to try it again after the plugs are on so I can at least have a platform to work with... I'm just having problems with the internet.. and getting ahold of a printer!!!!

Any suggestions for the best way to do this... Im still getting thise pics ready btw

**one of the wires actually turned my windsheild wipers on** iTs aLivE! :)
 
*Update*

Upon my disoveries of Of the above diagram and another like it for obd2 (as well as a few cross references)...


A1-INJ1 INJECTOR#1 Brown, Battery Voltage with KOEO
A2-INJ4 INJECTOR#4 Yellow, Battery Voltage with KOEO
A3-INJ2 INJECTOR#2 Red, Battery Voltage with KOEO
A4-VTS VTEC solenoid - Orange/white -to- GRN/YEL
A5-INJ3 INJECTOR#3 - light Blue - to one of 4 or 5 solid blue
A6-PO2SHTC O2 sensor heating element Org/black to black/white
A7-FLR1 fuel pump Grn/BLue
A8-empty A7 and A8 have the same circurt, Grn/BLue

A9-IACV IAC valve - green/white to Blk/Blu,
A10-empty
A11-EGR Control Solenoid Valve (if the ECU has it) Red, n/a
A12-FANC engine coolant temp switch yellow/green - to - green
A13-MIL MIL (check engine light) green/orange
A14-empty
A15-ACC (a/c compressor clutch) black/red
A16-ALT C alternator Wht/Grn, n/a
A17-IAB IAB Solenoid Pink, - to pink /blue
A18-Org/Red, Transmission Control Module (A/T), n/a
A19- Intake control solenoid, - white
A20-PCS EVAP purge control solenoid Red
A21-ICM Ignition Control Module output signal, red/green
A22-Igniter, same as A21
A23-PG1 ground Black, Power ground, less than 1V
A24-PG2 ground same as A23
A25-IGP2 to main relay and to ground Yel/blk,
A26-LG1 gound Blk/red, less than 1V

B1-IGP2 to pin A25 Yel/Blk, Battery positive from Main relay, Battery Voltage with KOEO
B2-LG2 ground to shields for CYP & TDC Brown/Blk, <1V
B3-Orange, upshift/downshift comparative input, n/a
B4-Pink, upshift/downshift comparative input, n/a
B5-ACS a/c switch Blu/red a/c
b6- empty
B7-Light green, Park/Neutral (civic)
B8-PSPSW PSP switch Red/Green, Power steering oil pressure switch, 0V KOEO; Battery Voltage KOER While slowly turning steering wheel
B9-STARTER SIGNAL starter signal Blue/red, Battery Voltage in the START position (clutch depressed on M/T models)
B10-VSS vehicle speed sensor Orange or yellow/blue,
B11-CYP P CYP(#1 piston position) -P Orange - to yellow, CYP sensor input, n/a
B12-CYP M CYP -M White, CYP sensor signal, n/a
B13-TDC P TDC(top dead ceter) -P Org/Blue, TDC sensor input, n/a
B14-TDC M TDC -M Wht/Blue, TDC sensor signal, n/a
B15-CKP P CKP(crank position) -P Blu/yellow, CKP Sensor input, n/a
B16-CKP M CKP -M Blu/yel, CKP Sensor ground, n/a

D1-VBU Back Up Power Wht/Yel or white/blue, Battery positive From battery through Fuse Box, Battery Voltage at ALL times
D2-BKSW brake switch Grn/wht, Battery voltage at all times
D3-KS Knock Sensor Red/Blue,
D4-SCS service check connector Brown/Wht, ~5V (M/T); ~11V (A/T)
D5-empty
D6-VTM VTEC pressure switch Light Blue, n/a
D7-TXD/RXD (data link connector) Light Green/Red, n/a
D8-empty
D9-ALT F alternator Wht/Red, Alternator Charging Signal, ~4.5V KOEO; Decreases under Electrical load (Headlights & rear defogger on) At warm idle
D10-ELD electric load detector input Grn/red,
D11-TPS (throttle position sensor) Signal Red/Blk, ~0.5V KOEO with throttle fully closed; ~4.5V KOEO with throttle fully open
D12-Wht/Blk, EGR Valve Lift sensor, ~1.2V KOEO
D13-ECT (engine coolant temp) sensor input red/white, ~5V KOEO (varies with temperature)
D14-PHO2S O2 sensor White, heated 02 sensor Signal, 0.4-0.5V when ignition is turned on; drops to less than 0.1V within 2 minutes
D15-IAT Intake Air Temperature sensor signal Red/Yel, .05-4.5V KOEO(Varies with temperature)
D16-VREF (no info)
D17-MAP Map Signal Wht/Blu to white/yellow, ~3V KOEO (Varies with Temperature)
D18-white/red, Transmission Control Module (A/T Only), n/a
D19-Red/Wht, to yellow white Reference Voltage, ~5V KOEO
D20-Yel/Wht, to yellow/blue Reference Voltage, ~5V KOEO
D21-Blue/Wht to green/white, Sensor ground, <1V
D22-Green/Wht,to green/blue Sensor ground, <1V

heres the obd1chart to cross reference with the obd2 one above!
obd1.pin.schematics.gif

This is by direct request from YBLEGAL!
Im getting another shot tomorrow and the next so please give me your 2 cents!!!
p.s Still workin on those pix
 
BumP sorry the blue colors mean they are double checked and are obd1PLUG to obd2 Wire Color

The black ones are correct i believe
 
UPDATE!! adviCE?

The last week I have spent wiring my obd1 plugs to my obd2 gsr accordingly with both the above manuals and a helm's.

I then took my obd2 LS engine harness.. plugged it up to the shock towers on both sides and connected the black thick wire to the underhood relay fuse box.. And hooked up a battery.. finally got the windows up and played with my winsheild wipers a little..:cool:

Then I took my ignition to acc and i heard a few clicks.. BUT NO FUEL. curious to see what would happen, I turned the igniton switch to the start positon and MY MAIN RELAY STARTED WHINING.:eek:

went back to the ecu and diagrams and noticed that there are two Green/blue wires coming from under the dash one of which is fuel pump relay the other, sensor ground... I disconnected the two in an attempt to switch them but accidently let one of them touch the ecu bracket (grounded it) and the whining from the relay started.. but then fuel started dumping out of my fuel filter!? at the same time?:(

I've never noticed this whine in any hondas I've had and im wondering if its normal?:confused:

Do i have to have everything connected in order for my fuel pump to engage?

ALSO.. there are four connectors on my pass. side gsr shock tower.. Only three of which connect to the LS... which is the fourth... could that be my knock sensor? it's a two wire plug:huh:

I WILL HAVE PIX UP BY MONDAY!

I would like some advice but even if i get none i will still post my progress and hopefully some one will need it.. thanks:D
 
I would just recommend you connect the factory ecu plugs back into place and color match them for the most part and then use a ecu jumper or even make one. I have a bunch of Obd-2a/b ecu plugs that I use for my conversions so if you need a set pm me, Peace!
 
570 Views and no oNe Has had a "main relay whining" problem!?

I'm completely stumped and I have A.S.E techs telling me it's normal but I know It's NOT...
any ideas at all are appreciated... :(
 
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