Tacoma_TDI
Well-known member
I'm looking to start a discussion to compile a definitive list of what is needed to create/modify the ALH harness to create a "standalone" setup for those doing TDI swaps, as well as have some questions answered that I'm sure others will come across in the future. The only definitive list of sensors/plugs I've been able to find to date is from Fast Forward Automotive, but I'm wanting to confirm this with other members. So, here we go (slight variation from FFA):
1. ECU
2. +12V Battery
3. Glow Plug Relays
- High Heat Output Relay
- Low Heat Output Relay
4. MAP Sensor
5. MAF Sensor (can delete with tune)
6. N75 Turbo Valve
7. N239 Anti-Shudder Valve (can delete with tune)
8. N18 EGR Valve (can delete with tune)
9. Alternator Plug
10. Glow Plug Rail
11. Coolant Glow Plugs (not necessary, suggested for cooler temps)
12. Oil Pressure Sensor
13. Water Temp Sensor
14. Injector Pump Plug
15. Crank Position Sensor
16. Needle Lift Sensor
17. Dash Lights
- Glow Plug
- Check Engine Light
- Tachometer (unsure how to interface with Tacoma cluster...)
- Speedometer (unless using non-TDI vehicle's original cluster)
- Oil Pressure Warning
18. OBD Port
19. Accelerator Pedal
Is there anything here that I'm missing or needs changing? Also, I have a few questions I've come across while tearing the stock harness apart that I was hoping someone could answer me, so bear with me lol.
First, in my OBD port I have (had) a wire going into Pin 1 that came from the cooling fan module plug, which has since been removed. Is this pin necessary?
Second, I've noticed in the Haynes manuals that the brake and the clutch have wires going into the ECU. Can these be removed or must they be interfaced with the vehicle they're going into?
Third, is the "Voltage Supply Relay" necessary? What relays, aside from the glow plug relays, are necessary?
Lastly, would anyone happen to know what "AC/ALT Dash Con" would signify?When I removed the electric fan module I noticed that two wires coming from the alternator went into the plug going to the fan control module, yet the Haynes manual shows the wires (4) going into either the ECU (2) or power/ground.
Thanks in advance for any insight people can offer. Looking to make this a super helpful thread for people doing these swaps in the future. Cheers!
1. ECU
2. +12V Battery
3. Glow Plug Relays
- High Heat Output Relay
- Low Heat Output Relay
4. MAP Sensor
5. MAF Sensor (can delete with tune)
6. N75 Turbo Valve
7. N239 Anti-Shudder Valve (can delete with tune)
8. N18 EGR Valve (can delete with tune)
9. Alternator Plug
10. Glow Plug Rail
11. Coolant Glow Plugs (not necessary, suggested for cooler temps)
12. Oil Pressure Sensor
13. Water Temp Sensor
14. Injector Pump Plug
15. Crank Position Sensor
16. Needle Lift Sensor
17. Dash Lights
- Glow Plug
- Check Engine Light
- Tachometer (unsure how to interface with Tacoma cluster...)
- Speedometer (unless using non-TDI vehicle's original cluster)
- Oil Pressure Warning
18. OBD Port
19. Accelerator Pedal
Is there anything here that I'm missing or needs changing? Also, I have a few questions I've come across while tearing the stock harness apart that I was hoping someone could answer me, so bear with me lol.
First, in my OBD port I have (had) a wire going into Pin 1 that came from the cooling fan module plug, which has since been removed. Is this pin necessary?
Second, I've noticed in the Haynes manuals that the brake and the clutch have wires going into the ECU. Can these be removed or must they be interfaced with the vehicle they're going into?
Third, is the "Voltage Supply Relay" necessary? What relays, aside from the glow plug relays, are necessary?
Lastly, would anyone happen to know what "AC/ALT Dash Con" would signify?When I removed the electric fan module I noticed that two wires coming from the alternator went into the plug going to the fan control module, yet the Haynes manual shows the wires (4) going into either the ECU (2) or power/ground.
Thanks in advance for any insight people can offer. Looking to make this a super helpful thread for people doing these swaps in the future. Cheers!
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