ns3e

Final problem to resolve:

I've searched for schematics and information. I have a 05 Engine harness with a 03 ECU. I have already swapped the O2 to a narrowband but the wiring doesn't seem correct as it is throwing a heater code. Does anyone have information as to how to wire or re-wire to have the 03 civic ECU see the information it need from the narrowband by using the 05 engine harness?

ns3e

I believe that all I have to do is locate the ends of the 4 wires going to and from the oxygen sensor as both 2003 and 2005 have 4-wire sensors. I'm having trouble finding and locating a wiring schematic for the new 2004-2005 Civics. I checked voltage on all wires going to the sensor and none of the wires are supplying 12V. The pins must be in a different location on the 2003 as compared to 2005..

bbarbulo

I'll just leave this here...


​​​​​​​01-03 Honda Civic EX M/T ECU Pinouts

Connector A (31 Pins) 01-03 Civic EX M/T
1-blk/wht-Primary O2 sensor heater control
2-yel/blk-Power Source
3-yel/blk-Power source
4-blk-Power ground
5-blk-Power ground
6-wht-Primary O2 sensor
7-blu-Crankshaft position
8-yel-Sensor return volt
9-red/blu-Knock sensor
10-grn/yel-Sensor ground
11-grn/wht-Sensor ground
12-blk/red-Idle air control valve
13-wht/blk-EGR Valve position VTEC ONLY
14-blk/wht-Secondary O2 sensor heater control
15-red/blk-Throttle position sensor
18-wht/grn-Vehicle speed sensor
19-grn/red-MAP Sensor
20-yel/blu-Sensor Voltage Supply
21-yel/red-Sensor Voltage Supply
23-brn/yel-Logic ground
24-brn/yel-logic ground
25-wht/red-Secondary O2 Sensor
26-grn-Top dead center sensor
27-brn-Igniton coil 4
28-wht/blu-coil 3
29-blu/red-coil 2
30-yel/grn-coil 1

Connector B (24 Pins) 01-03 Civic EX M/T
2-yel-Fuel injector 4
3-blu-Injector 3
4-red-Injector 2
5-brn-Injector 1
6-grn-Radiator fan control
7-red/blk-A/T Pressure control solenoid valve A
8-red/wht-Engine Coolant sensor
9-blu/blk-VTEC Oil pressure switch VTEC ONLY
10-wht/blu-Alternator L Signal
13-wht/red-Alternator FR Signal
14-blu/red-EGR Valve VTEC ONLY
15-grn/yel-VTEC Solenoid valve
16-blk/red-A/T Pressure control solenoid valve B
17-red/yel-Intake air temp sensor
18-wht/grn-Alternator control
21-yel/blu-EVAP Canistor purge valve

Connector E (31 pins) 01-03 Civic EX M/T
1-grn/yel-Immobilizer fuel pump relay
2-wht/red-Secondary O2 Sensor EX Only
3-brn/yel-Logic ground
4-pnk-Sensor ground
5-yel/blu-Sensor voltage source
6-blk/wht-Secondary O2 sensor heater control EX Only
7-red/yel-PGM-FI main relay 1
9-yel/blk-Ignition input signal
12-blu/orn-Cruise control signal
13-wht/blu-Interlock control unit
14-lt grn-Fuel tank pressure sensor
15-grn/red-Electrical load detector
16-lt grn/blk-Power steering pressure switch
18-red-A/C Clutch
20-blu/red-EVAP bypass solenoid valve
21-lt grn/red-EVAP Canister shut valve
22-wht/blk-Brake pedal position switch
23-lt blu-K line
24-yel-Multiplex control unit comm line
26-blu-Engine speed pulse
27-red/blu-Immobilizer code
29-brn-Service check signal
30-red/wht-Write enable signal
31-grn/orn-MIL or check engine light enable


04-05 Honda Civic EX M/T ECU Pinouts

Connector A (31 Pins) 04-05 Civic EX M/T
1-grn Primary O2 (WB) sensor heater control
2-yel/blk-Power Source
3-yel/blk-Power source
4-blk-Power ground
5-blk-Power ground
6-red- Primary O2 (WB) positive
7-blu-Crankshaft position
8-yel-Sensor return volt
9-red/blu-Knock sensor
10-grn/yel-Sensor ground
11-grn/wht-Sensor ground
12-blk/red-Idle air control valve
13-wht/blk-EGR Valve position VTEC ONLY
14-blk/wht-Secondary O2 sensor heater control
15-red/blk-Throttle position sensor
16 -Primary O2 (WB) negative
18-wht/grn-Vehicle speed sensor
19-grn/red-MAP Sensor
20-yel/blu-Sensor Voltage Supply
21-yel/red-Sensor Voltage Supply
22 -wht Primary O2 (WB) sensor heater control positive
23-brn/yel-Logic ground
24-brn/yel-logic ground
25-wht/red-Secondary O2 Sensor
26-grn-Top dead center sensor
27-brn-Igniton coil 4
28-wht/blu-coil 3
29-blu/red-coil 2
30-yel/grn-coil 1

Connector B (24 Pins) 04-05 Civic EX M/T
2-yel-Fuel injector 4
3-blu-Injector 3
4-red-Injector 2
5-brn-Injector 1
6-grn-Radiator fan control
7-red/blk-A/T Pressure control solenoid valve A
8-red/wht-Engine Coolant sensor
9-blu/blk-VTEC Oil pressure switch VTEC ONLY
10-wht/blu-Alternator L Signal
13-wht/red-Alternator FR Signal
14-blu/red-EGR Valve VTEC ONLY
15-grn/yel-VTEC Solenoid valve
16-blk/red-A/T Pressure control solenoid valve B
17-red/yel-Intake air temp sensor
18-wht/grn-Alternator control
21-yel/blu-EVAP Canistor purge valve

Connector E (31 pins) 04-05 Civic EX M/T
1-grn/yel-Immobilizer fuel pump relay
2-wht/red-Secondary O2 Sensor EX Only
3-brn/yel-Logic ground
4-pnk-Sensor ground
5-yel/blu-Sensor voltage source
6-blk/wht-Secondary O2 sensor heater control EX Only
7-red/yel-PGM-FI main relay 1
8 -org Primary O2 sensor relay
9-yel/blk-Ignition input signal
12-blu/orn-Cruise control signal
13-wht/blu-Interlock control unit
14-lt grn-Fuel tank pressure sensor
15-grn/red-Electrical load detector
16-lt grn/blk-Power steering pressure switch
18-red-A/C Clutch
20-blu/red-EVAP bypass solenoid valve
21-lt grn/red-EVAP Canister shut valve
22-wht/blk-Brake pedal position switch
23-lt blu-K line
24-yel-Multiplex control unit comm line
26-blu-Engine speed pulse
27-red/blu-Immobilizer code
29-brn-Service check signal
30-red/wht-Write enable signal
31-grn/orn-MIL or check engine light enable

ns3e

Thank you. Listed below are the wires that I can find locations and descriptions to. I still have to find out more as the sensor has 4 wires. Is it just a regular sensor ground/power wire going to the O2? After the auto to manual swap the computer is throwing a Primary O2 heater code. I just need to run the right wires to and from the O2.

Connector A (31 Pins) 01-03 Civic EX M/T
1-blk/wht-Primary O2 sensor heater control
6-wht-Primary O2 sensor
22- Does not exist

Connector A (31 Pins) 04-05 Civic EX M/T
1-grn Primary O2 (WB) sensor heater control
6-red- Primary O2 (WB) positive
22 -wht Primary O2 (WB) sensor heater control positive


Motor and harness: 04-05 Civic
ECU: 01-03 Civic
O2 Sensor: Narrowband to send correct signal to ECU

bbarbulo

this explains why only 2 wires go to the ECU

ns3e

So is there a reason why the 01-03 ECU is throwing a CEL even after installing the Narrowband O2 that it needs?

bbarbulo

what's the code?

ns3e

P0135 code.

bbarbulo

do you have the correct wires going to the correct places?

the two wires that go to the ECU are sensor output and heater trigger. is that what's hooked up to the O2?

found a ton of great diagrams here http://autowiring.org/wiring/1999-ci...g-diagram.html

bbarbulo

also, I believe according to the wiring diagrams I'm seeing that the heater gets voltage from the fusebox (through the main relay) so check to see if that wire is getting 12v with key on.

ultimately it comes down to tracing out two wires from the heater. you have power from the fuse box, and the other is heater control (ground) at the ECU it looks like. so bust out the multimeter and check it.

ns3e

With a multimeter:
Red - nothing
Red/yellow - nothing
Green - ground
White - nothing

The thick white wire should be getting 12V right?

ns3e

Whoa, my phone sure did make the photo big. So:

With a multimeter:
Red - nothing
Red/yellow - nothing
Green - ground
White - nothing

The thick white wire should be getting 12V right?

bbarbulo

red goes to A6, that's the output signal from the O2 sensor (so should be nothing on it)

red yellow is sensor ground

green is heater control input

white is circuit E70

oh fack, I just found some better wiring diagrams - there is more going on here than jumbled up wires.

bbarbulo

what year is the actual car? is there a A/F sensor relay or not? the wiring diagram above shows 04-05 had an air/fuel sensor relay, and 01-03 didn't have that.

you could just wire it according to an 01-03 diagram. Fuse 4 positive to the heater, the other end of the heater to the ECU heater control ground A1. That takes care of the heater. Then pin A10 on the ECU to O2 sensor ground, and O2 sensor output to pin A6 (shielded) - and that's that. It is now an entire 01-03 narrow band setup.

note you have to move pin A16 from the 04-05 harness and merge it with A10.

ns3e

Thanks for your help so far bro! I owe you a beer or something!

The car is a 2005 Civic LX (originally auto)
The transmission and ECU is from a 01-03 Civic (5speed)

I didn't know about the change in O2 sensors until after I finished the swap when the CEL came on. Yes, there is an A/F sensor relay. I'll work on it in the morning and will let you know!

bbarbulo

lol I see what's happening then.

the relay no longer gets a command from the ECU. 04-05s drove that relay via conditional ground on pin E8 of the ECU. Since you don't have pin E8 on a 01-03 ECU, the heater relay is no longer functional. So wire the heater positive (white wire) at the A/F relay to the relay solenoid 'hot' (black/orange wire) at the A/F relay. Literally cut and solder the wires together, heatshrink - and code should be gone if all the other wiring is correct.

Civic2004ex

Hi , i have this issue,, i have a 2004 civic ex with manual transmission, i swapped the ecu with the immobilizer but the ecu and immobilizer was from a 2002 civic ex Manual transmission. and im receiving the p0135 Code. I read about the wideband and narrowband and i just need help on which cables i need to connect together, who can send me a picture to my email carlosmm28@aol.com or my number 3037252637