Wire harness help 1993 64,000mi
07-10-17, 06:53 PM
#1
MADROTORS
Thread Starter
Wire harness help 1993 64,000mi
My friend just picked up this fine automobile and it had some known issues. I have only worked on JDM RHD fd so there are a few small difderences. I have beed digging a little and a found a couple small plugs behind the ECU with no where to be plugged. I also found what appears to be some cut and repaired or tapped over wires on the main harness. Is there a possible modification that would warrant cutting the main harness? The current problem is the fans dont come on at temp. There was also a loose ground on the ecu. I have checked the condition of the wires to the thermal switch and the AC fan does work when AC is activated.
07-10-17, 08:41 PM
#2
RX-7 Bad Ass
iTrader: (55)
Read up on the fan recall, that's some of the fan recall wiring. That cut wire could be from an old fan mod, you're going to have to get the wiring diagram out and figure out which wire is cut and what it goes to.
Dale
Dale
07-11-17, 06:28 AM
#3
The black plug your holding looks almost identical to the plug that goes into the black of the center hvac panel in the middle of the dash, why it's down there I have no idea......if coming from the dash harness could it be cruise control or el unit plug?
Last edited by OG BBF; 07-11-17 at 06:42 AM.
07-11-17, 07:29 PM
#4
Super Moderator
iTrader: (1)
Possible Wire Identification
From the photos you included and based upon my ‘94 schematic diagrams, the broken wires are as follows:
Blue/Yellow Stripe (L/Y) wire cut:
1. From ECU connector B1-01-1.
2. Originates at Pin 1N - Vehicle Speed Sensor / Mileage Switch.
2.a. Goes to Steering Pressure Sensor via Connectors X-12 & B1-21.
2.b. Goes to Instrument Cluster Input #30 via Connectors X-06 & C1-01. Connects to CPU and Speedometer (Speedometer circuit board) via Pin 4C.
3. From ECU connector B1-01-4.
4. Originates at Pin 4O – Solenoid Valve (EGR).
4.a. Goes to EGR Solenoid Valve via Connector B1-29.
5. Originates at Pin 4V – Solenoid Valve (Turbo Precontrol).
5.a. Goes to Turbo Pre-control Solenoid Valve via Connector B1-37.
6. Verify which pin(s) were cut: 1N, 4O, or 4V, or a combination of any three.
Blue/Lt Blue Stripe (L/LB) wire cut:
1. Unknown.
2. Could be Blue/Sky Blue) ?
Brown (BR) wire cut/repaired/taped:
1. From ECU Connector B1-01-1.
2. Originates at Pin 1G – Igniter (Trailing Front Rotor).
2.a. Goes to Igniter via Connector B1-09.
3. Wire could be connected to something else, must remove electrical tape.
Black/Red wire:
1. From ECU Connector B1-01-4.
2. Originates at Pin 4F – Solenoid Valve (Split air bypass).
2.a. Goes to Split Air Bypass Solenoid Valve via Connector B1-23.
Blue (with small silver ring) wire:
1. Verify this wire is undamaged. The Black/Red wire in front of it gives the illusion that it is cut.
Refer to Pg Z-35 through Z-38 for detailed info on ECU terminal (pin) voltages.
Again, my research was based upon reading the ‘94 electrical diagram manual. Please refer to the ‘93 schematic and verify these wires are indeed severed to the correct components (Split Air Bypass & Turbo Precontrol Solenoids). Perhaps this was a mod for a single or non-sequential turbo? Is this a stock '93 FD? I cannot speculate why the Brown wire was cut then repaired.
What are the other “known issues” that your friend has with this particular FD? Is it a JDM or USDM market FD? Your mention of JDM experience is a little misleading. What other wires were cut, repaired, and/or capped off?
Best of luck and keep us posted on your findings!
Cheers,
George
Blue/Yellow Stripe (L/Y) wire cut:
1. From ECU connector B1-01-1.
2. Originates at Pin 1N - Vehicle Speed Sensor / Mileage Switch.
2.a. Goes to Steering Pressure Sensor via Connectors X-12 & B1-21.
2.b. Goes to Instrument Cluster Input #30 via Connectors X-06 & C1-01. Connects to CPU and Speedometer (Speedometer circuit board) via Pin 4C.
3. From ECU connector B1-01-4.
4. Originates at Pin 4O – Solenoid Valve (EGR).
4.a. Goes to EGR Solenoid Valve via Connector B1-29.
5. Originates at Pin 4V – Solenoid Valve (Turbo Precontrol).
5.a. Goes to Turbo Pre-control Solenoid Valve via Connector B1-37.
6. Verify which pin(s) were cut: 1N, 4O, or 4V, or a combination of any three.
Blue/Lt Blue Stripe (L/LB) wire cut:
1. Unknown.
2. Could be Blue/Sky Blue) ?
Brown (BR) wire cut/repaired/taped:
1. From ECU Connector B1-01-1.
2. Originates at Pin 1G – Igniter (Trailing Front Rotor).
2.a. Goes to Igniter via Connector B1-09.
3. Wire could be connected to something else, must remove electrical tape.
Black/Red wire:
1. From ECU Connector B1-01-4.
2. Originates at Pin 4F – Solenoid Valve (Split air bypass).
2.a. Goes to Split Air Bypass Solenoid Valve via Connector B1-23.
Blue (with small silver ring) wire:
1. Verify this wire is undamaged. The Black/Red wire in front of it gives the illusion that it is cut.
Refer to Pg Z-35 through Z-38 for detailed info on ECU terminal (pin) voltages.
Again, my research was based upon reading the ‘94 electrical diagram manual. Please refer to the ‘93 schematic and verify these wires are indeed severed to the correct components (Split Air Bypass & Turbo Precontrol Solenoids). Perhaps this was a mod for a single or non-sequential turbo? Is this a stock '93 FD? I cannot speculate why the Brown wire was cut then repaired.
What are the other “known issues” that your friend has with this particular FD? Is it a JDM or USDM market FD? Your mention of JDM experience is a little misleading. What other wires were cut, repaired, and/or capped off?
Best of luck and keep us posted on your findings!
Cheers,
George
07-17-17, 10:50 AM
#5
MADROTORS
Thread Starter
oh man thank you very much for this write up. I never would have expected this much info lol. I have downloaded the printout for ecu and stuff I haven't had time to dig into the harness and verify anything yet. it looks like the previous owner went ahead and deleted all the cali emissions stuff too so I have to dig through the car and make sure I have everything I still need to keep it running right. I'm pretty sure I have figured out the current issue. she was boiling over at operating temp. had new caps on it. since they did a half asked ats delete the filler neck cap they put on there was crap and made from plastic and the inside of it was chipped away and the cap wasn't actually sealing. the other issue was the fan was never coming on. I have an FC thermal switch in the mail and my guess is the car would boil over before reaching temp or the thermal switch is bad. anyway thank you very much for all the info i'll keep working on it.
From the photos you included and based upon my ‘94 schematic diagrams, the broken wires are as follows:
Blue/Yellow Stripe (L/Y) wire cut:
1. From ECU connector B1-01-1.
2. Originates at Pin 1N - Vehicle Speed Sensor / Mileage Switch.
2.a. Goes to Steering Pressure Sensor via Connectors X-12 & B1-21.
2.b. Goes to Instrument Cluster Input #30 via Connectors X-06 & C1-01. Connects to CPU and Speedometer (Speedometer circuit board) via Pin 4C.
3. From ECU connector B1-01-4.
4. Originates at Pin 4O – Solenoid Valve (EGR).
4.a. Goes to EGR Solenoid Valve via Connector B1-29.
5. Originates at Pin 4V – Solenoid Valve (Turbo Precontrol).
5.a. Goes to Turbo Pre-control Solenoid Valve via Connector B1-37.
6. Verify which pin(s) were cut: 1N, 4O, or 4V, or a combination of any three.
Blue/Lt Blue Stripe (L/LB) wire cut:
1. Unknown.
2. Could be Blue/Sky Blue) ?
Brown (BR) wire cut/repaired/taped:
1. From ECU Connector B1-01-1.
2. Originates at Pin 1G – Igniter (Trailing Front Rotor).
2.a. Goes to Igniter via Connector B1-09.
3. Wire could be connected to something else, must remove electrical tape.
Black/Red wire:
1. From ECU Connector B1-01-4.
2. Originates at Pin 4F – Solenoid Valve (Split air bypass).
2.a. Goes to Split Air Bypass Solenoid Valve via Connector B1-23.
Blue (with small silver ring) wire:
1. Verify this wire is undamaged. The Black/Red wire in front of it gives the illusion that it is cut.
Refer to Pg Z-35 through Z-38 for detailed info on ECU terminal (pin) voltages.
Again, my research was based upon reading the ‘94 electrical diagram manual. Please refer to the ‘93 schematic and verify these wires are indeed severed to the correct components (Split Air Bypass & Turbo Precontrol Solenoids). Perhaps this was a mod for a single or non-sequential turbo? Is this a stock '93 FD? I cannot speculate why the Brown wire was cut then repaired.
What are the other “known issues” that your friend has with this particular FD? Is it a JDM or USDM market FD? Your mention of JDM experience is a little misleading. What other wires were cut, repaired, and/or capped off?
Best of luck and keep us posted on your findings!
Cheers,
George
Blue/Yellow Stripe (L/Y) wire cut:
1. From ECU connector B1-01-1.
2. Originates at Pin 1N - Vehicle Speed Sensor / Mileage Switch.
2.a. Goes to Steering Pressure Sensor via Connectors X-12 & B1-21.
2.b. Goes to Instrument Cluster Input #30 via Connectors X-06 & C1-01. Connects to CPU and Speedometer (Speedometer circuit board) via Pin 4C.
3. From ECU connector B1-01-4.
4. Originates at Pin 4O – Solenoid Valve (EGR).
4.a. Goes to EGR Solenoid Valve via Connector B1-29.
5. Originates at Pin 4V – Solenoid Valve (Turbo Precontrol).
5.a. Goes to Turbo Pre-control Solenoid Valve via Connector B1-37.
6. Verify which pin(s) were cut: 1N, 4O, or 4V, or a combination of any three.
Blue/Lt Blue Stripe (L/LB) wire cut:
1. Unknown.
2. Could be Blue/Sky Blue) ?
Brown (BR) wire cut/repaired/taped:
1. From ECU Connector B1-01-1.
2. Originates at Pin 1G – Igniter (Trailing Front Rotor).
2.a. Goes to Igniter via Connector B1-09.
3. Wire could be connected to something else, must remove electrical tape.
Black/Red wire:
1. From ECU Connector B1-01-4.
2. Originates at Pin 4F – Solenoid Valve (Split air bypass).
2.a. Goes to Split Air Bypass Solenoid Valve via Connector B1-23.
Blue (with small silver ring) wire:
1. Verify this wire is undamaged. The Black/Red wire in front of it gives the illusion that it is cut.
Refer to Pg Z-35 through Z-38 for detailed info on ECU terminal (pin) voltages.
Again, my research was based upon reading the ‘94 electrical diagram manual. Please refer to the ‘93 schematic and verify these wires are indeed severed to the correct components (Split Air Bypass & Turbo Precontrol Solenoids). Perhaps this was a mod for a single or non-sequential turbo? Is this a stock '93 FD? I cannot speculate why the Brown wire was cut then repaired.
What are the other “known issues” that your friend has with this particular FD? Is it a JDM or USDM market FD? Your mention of JDM experience is a little misleading. What other wires were cut, repaired, and/or capped off?
Best of luck and keep us posted on your findings!
Cheers,
George
07-17-17, 12:31 PM
#6
Super Moderator
iTrader: (1)
oh man thank you very much for this write up. I never would have expected this much info lol. I have downloaded the printout for ecu and stuff I haven't had time to dig into the harness and verify anything yet. it looks like the previous owner went ahead and deleted all the cali emissions stuff too so I have to dig through the car and make sure I have everything I still need to keep it running right. I'm pretty sure I have figured out the current issue. she was boiling over at operating temp. had new caps on it. since they did a half asked ats delete the filler neck cap they put on there was crap and made from plastic and the inside of it was chipped away and the cap wasn't actually sealing. the other issue was the fan was never coming on. I have an FC thermal switch in the mail and my guess is the car would boil over before reaching temp or the thermal switch is bad. anyway thank you very much for all the info i'll keep working on it.
If your AST is eliminated then check out the AST delete threads. There should be plenty of information abound there. Be aware though if you suspect the coolant boiling over under normal temps then consider a blown coolant seal. Again, there are multiple threads that cover this topic. But first, eliminate all the normal coolant line issues as you pointed out. Do keep us posted on your progress!
Cheers,
George
Last edited by Gen2n3; 07-17-17 at 06:55 PM.
