barebones harness modifications?

Runninwild

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AAZ swapped 2000 tacoma
Hey I just had a look at the alh pinout sticky. From what I gather these are the wires I need to keep and everything else can be cut/deleted with a tune?

The 6 wires to the obd2 dlc port

the 7 wires for the glow plug relay

T14A connector pins 5 ( fused 30amp), 6 (fused 10amp) and 9 ground. This looks to be the connector for the factory sensors. Can this all be deleted if running external gauges?

T10 Orange pin 5 for the map/iat

T10 Blue keep everything for the pedal

T10 white pin 9 for map/iat

T10 black completely cut out?

T6 brown keep everything but pin 3 for the starter signal?

The only things I didn't notice on the pinout was for the n75 valve. is this needed without vnt or can a tuner delete it? or anything for a crank sensor

I also didn't see a signal wire on the cluster pinout to throw the cel, or if there is a signal wire for a glow plug light?

Can anyone confirm if this is correct or if there is anything else I would need to do? I think im oversimplifying it
 

CasaEd

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If you are using a wastegate turbo you need the n75, it's not shown in the ALH pinout because the wires for it do not go into the car. The pin number is 62 in the ecu plug.
You don't say what vehicle you are converting the loom for, if your vehicle is not a VW with Can-Bus then you don't need to connect that in the OBD plug.
 

Runninwild

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AAZ swapped 2000 tacoma
Its going in a 2000 tacoma. All i really need from the ecu is to run the engine and tach output maybe
 

Runninwild

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AAZ swapped 2000 tacoma
I'm going to use this thread to document everything. I've started peeling open my harness. I need to start somewhere so why not with the T connectors. Can someone confirm this is correct?

The wires on my t10 orange connector are different colours and I don't have a pin5 for map/iat. I assume this means I have a golf or jetta harness and the entire plug can be cut out?

T10 blue wires are again completely different. I don't have the other side of any of the t10 connectors. I assume this goes to a short harness that then plugs into the accelerator pedal and i'd obviously keep everything intact on this plug?

T10 white I don't have the pin 9 map/iac so this can be completely cut out?

T10 black can be completely cut out if I don't care about cruise control?

T6 brown Pin 1 would be to switched 12v to turn on ecu
Missing pin 2, it looks like the glow plug relay is integrated into my harness?
Pin 3 thicker wire for starter can be removed
Pin 4 Fat wire to 30a fuse
Pin 5 and pin 6 goto a single 10amp fuse?


I think im missing the t14a (is this a 10pin plug on the small plug harness?) and the T16 obd parts of my harness.
 

AndyBees

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Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
T14 means 14 pins, of course they are not all used, even in the OE set-up!

Back in 2009-10-11-12 when I was doing my project, finding someone to share this info was like finding a chicken with teeth. So, I copied (and enlarged) the Bentley schematics that applied to my donor engine and all the wiring that come with it. I spent hours and hours deciphering that stuff. Without all the details, when I was sitting with family in Chemo, Dr office, Hospital, Nursing Home, etc., I would read electrical schematics, make notes, type up notes, search web site, etc.

So, in my opinion, even with the info in the sticky, you would be ahead to commence putting together notes for a ring-binder. That binder will be your "owner's manual" for future trouble shooting.
 

Runninwild

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AAZ swapped 2000 tacoma
Sounds like a good way to take your mind off things. I Hope everything is well now
So ive found a ecu connector pinout online and have figured some stuff out without having to trace back connector plugs.

I have 2 smaller ecu plug harnesses. One is more or less intact with a couple plugs cutoff (T14a and something else I havnt figured out yet). The other has all its insulation stripped off and luckily for me is already modded. The t14a connector has also been cut from this and has been replaced with a 2 pin plug with 2 wires going to a single pin. These are the red/purple and yellow/black from the ip plug which tie into pins 1 and 2 on the big connector and a 30amp fused power source. The yellow/black is the ip turn on signal i believe? this should be 12v switched with ignition not constant power right? The only issue I can find with this modified harness is 2 wires were cut from the temp sensor plug. The ground and the gauge output. Pretty easy fix. Should I tie the ground into pin 86 brown/yellow which leads into the shielded wires for needle lift and rpm sensors or just run a separate ground wire? The other issue is the needle lift sensor is a 2 wire plug but I have a nub of a black wire poking out the top of the shielding that had been cut. Is this anything important? looks to me like its just an unused ground?

onto the big plug harness. I havnt touched anything yet but this is the plan from the pinout I found. The only issue is the pinout only lists 28 pins yet I count 46 wires? Are the other 18 wires for anything significant? Let me know if this looks right and ill start hacking it up


pin 1 & 2 main 12v input, tie in with purple/red and yellow/black from small harness and run to 30amp constant fuse
Pin 4 & 5 grounds keep Are these grounds for sensors or just hook them to ground?
Pin 12 throttle keep
Pin 16 obd 2 k line keep and connect to Toyota obd2 port
Pins 18/20 vss and relay 109 cut out
Pin 24 to CEL light on cluster
Pin 27 to tach signal on cluster
Pin 30 maf cut out
Pin 31 map/iat keep
Pin 32 brakes cut out
Pin 33 glow plug relay signal keep
Pin 37 turn on signal, wire to 12v switched ignition?
Pin 40 wait to start is this the glowplug light on dash?
Pin 42 glowplugs keep
Pin 49 maf cut out
Pins 50/51 throttle keep
Pin 52 map/iat keep
Pin 62 n75 keep? Is this necessary or can it be deleted with a tune?
Pin 63 throttle keep
Pin 65 brakes cut out
Pins 69/70 throttle keep
Pins 71/73 Map/iac keep

Then I also need switched 12v to pin 1 on n75 and pin 5 on the glowplug relay?
 
Last edited:

AndyBees

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Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
If you have an older version of Word (or maybe new one will be okay), I can send you the notes I have. They are in Word Perfect. That's why you may need an older version of Word to convert if you do not have Word Perfect.

I also have a lot of stuff in Excel spreadsheet.

Everything is based the 2002 Jetta/Golf.
 

CasaEd

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Curious as to why you don't want to power the ECU up and down the correct way ?
usually an ignition signal wire down pin 37 allows pin 18 to go to earth turning on the 109 relay to power the ECU, thats the best way in my opnion, but its your call. i also favour connecting brake and clutch signals to the ECU and I still don't understand why you want to lose the N75, this valve controls the turbo, whether it's wastgate or VNT to prevent overboosting and provide optimum perforfance from the turbo during all operating conditions.

As for the tacho signal that depends on whether you have an analog or digital tacho fitted
 

Runninwild

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AAZ swapped 2000 tacoma
From my understanding relay 109 is the main power feed for accessories. It cuts power to everything but the engine during cranking and then restores power? I dont see the need to reinvent the wheel with the trucks original wiring. I didn't receive relay 109 with my harness and I don't really see the point to installing one just to power up the ecu. A 12v switched keyed into the ignition should accomplish the same no? Is pin 37 12v actuated or ground actuated?

Isnt the n75 for controlling the vanes on a vnt? I dont really see how it would do anything on wastegate turbos? The wastegates are controlled by spring pressure. Does the n75 work like a manual boost controller? My engine didnt come with one but if it does work like a mbc it might be worth keeping?

Im planning on running compounds. First turbo will have its waste gate tied shut and be controlled with an external gate more then likely set to 10psi. The second turbo will be set somewhere between 25-30psi for a total of 35-40psi of boost. Im not quite sure how well an n75 would control the second turbo as it would always have 10psi it couldn't control.

As for the brake related stuff im not really planning on using cruise control. Any other reason to keep it?

Its a digital tach. I've heard online that the toyota tach works with the vw signal. If not I do have a dakota digital tach converter to make it work.
 

Runninwild

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AAZ swapped 2000 tacoma
sorry it looks like relay 109 is the load reduction and relay 100 is mainly just power to the ecu and sensors?

From you description pin 37 when given 12v activates a ground on pin 18 which then turns on relay 109 and energizes pins1/2 and all the other onboard sensors? will the ecu drain the battery if its hooked to constant 12v fused? I guess it wouldn't be a big deal to wire it in. do you know if there is aftermarket relay sockets for the 109 relay? or if the pigtail can be removed from the factory relay box?

Would you see any issue just replacing 109 with a standard 40amp relay? I'm thinking a 40amp fuse into a standard 40amp relay which then splits off to a 30amp fuse for ecu and a 10amp fuse for the sensors would be just as effective. I could probably even utilize one of the unused relays in my tacomas fuse box as ive deleted a few things (abs and a/c off the top of my head)
 

Hasenwerk

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1982 Cabriolet (BEW|VNT17|Stage4), 1989 VW TriStar Syncro soon-to-be CR TDI (CBEA), 2001 Ford Ranger Edge 4x4 (ALH|VNT17|R520|Stage4)
Just a suggestion, as I see you are struggling with a lot of basic concepts. Have you considered getting your harness professionally done? It doesn't cost that much and this way you know it is done correctly.

 
Last edited:

Runninwild

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how much isn't that much? I've got like 5 months to try and figure this out before I drop the engine in. I believe my plans are correct related to the pinout ive found and no one seems to really be correcting me on much other then on relay suggestions.

I'm not planning on cruise control so I don't need the brake wiring. no maf, egr or anti shudder valve. All I really plan to keep is the ip, maf, coolant sensor, crank sensor, n75 if necessary, the oil pressure switch and the needle sensor which according to the pinout I should be correct on my planning
 

CasaEd

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Your planning is ok from what i can see, the battery won't drain because the relay only energise's the ECU when switched on. You can use relay 109 or 100 to power the ECU. By all means delete the brake and clutch wires to the ECU, it will run, I've done a few PD engined Golf's and Ibiza's and the wires to the 80 pin plug are less than 30 with everything not needed taken out, i also remove the unused pins from the plug to keep the loom more tidy.
 

Runninwild

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AAZ swapped 2000 tacoma
I think ive got it figured out for the most part and have started cutting up the harness. There are a few wires that im not 100% sure on and I was hoping someone could confirm them for me. The harness is from a 5 speed as it has the 3 coolant glowplugs in it but my motor is an 01 auto (previous owner strips and flips tdis so just threw me a harness).

Anyways t10-orange pin 5 is a green/brown wire on my harness and lines up with pin27 on the ecu connector. The alh sticky lists pin5 on t10-orange as map/iac for beetle and n/a for golf or jetta. The other pinout I found lists pin 27 as the tach signal is this correct?


Another wire in question is pin 1 on t10-orange which is grey/white on my harness and lines up with ecu pin 16. alh sticky list it as n/a the other pinout lists it as the obd2 k-line is this correct?

And the final wire in question is t10-white pin 8 blue/green on my harness which lines up with ecu pin 40. Alh sticky lists this as a brake reservoir, the other pinout lists it as the wait to start light.

Another thing I noticed last night is I have 2 blue and black wires on the first row of wires (pin 6 to pin24) which are from pins 9 and pin 21. I popped the wires out of the connectors before tracing them to their locations. anyways one of them led to the glowplug relay and the other led to relay53 which I believe is for the horn. anyone know which came from what pin? it may not matter if the relay trigger is the one for the coolant glowplugs?

At any rate here is the pinout I created for the 80 pin connector. I gathered the function of each wire from both the pinouts so im not 100% sure on its accuracy. I have in total 21 wires from this connector I have kept including the power/grounds. Hopefully im right and didn't just destroy my harness lol

Yellow/black wires on sensors need 12v on relay 10amp fused ground activated from pin 18 blue/yellow wire
Pin 1 and 2 main power in 30amp fused relay ground trigger pin 18 blue/yellow
Pin 3 unused
Pin 4 and 5 ground


Pin 6 orange pin 3 t10-white can-low *cut*
pin 7 orange/black pin 2 t10-white can-hi *cut*
pin 8 unused
pin 9 blue/black to horn relay 53 or possibly glowplug relay *cut*
pin 10 unused
pin 11 brown/white pin 6 t10-white no idea *cut*
pin 12 yellow/green throttle *keep*
pin 13 unused
pin 14 black/white pin 3 t10-black cruise control *cut*
pin 15 unused
pin 16 gray/white obd2 k line to obd2 plug *keep*
pin 17 unused
pin 18 blue/yellow ground activation line from ecu to main 30amp harness relay
pin 19 unused
pin 20 blue/white pin 1 t10-black pin 1 cruise control *cut*
pin 21 blue/black to horn relay 53 or possibly glowplug relay
pin 22 black/brown to relay 100 load reduction *cut*
pin 23 unused
pin 24 unused cel? Missing from my harness inserted black/white from pin 14 for cel to programmer if possible


Pin 25 unused
pin 26 unused
pin 27 green/brown tach signal *Keep*
pin 28 green/white pin 2 t10-orange brake reservoir *cut*
pin 29 green no idea pin 7 t10-orange connector a/c *cut*
pin 30 red/green maf *cut*
pin 31 purple/red map/iat *keep*
pin 32 red/black pin 4 t10-black brake switch *cut*
pin 33 green/black glow plug signal *keep*
pin 34 blue/red pin 8 t10-orange a/c *cut*
pin 35 unused
pin 36 unused
pin 37 black/purple 12v switch ignition turn on signal for ecu
pin 38 brown/red pin 5 t10-white unused? *cut*
pin 39 unused
pin 40 blue/green wait to start, glowplug light on dash? *keep*
pin 41 unused
pin 42 unused
pin 43 unused

pin 44 red pin 2 t10-black cruise control *cut*
pin 45 blue/grey pin 1 t10-black cruise control *cut*
pin 46 white pin 9 t-10black cruise control *cut*
pin 47 green/purple pin 9 t10-white map/iat? No idea *cut*
pin 48 unused
pin 49 green maf *cut*
pin 50 grey/red throttle *keep*
pin 51 green/red throttle *keep*
pin 52 brown/blue map/iat *keep*
pin 53 unused
pin 54 unused
pin 55 unused
pin 56 unused
pin 57 unused
pin 58 unused
pin 59 unused
pin 60 unused
pin 61 red/blue 2 wire plug
pin 62 red/brown n75 *cut*


pin 63 white/blue throttle *keep*
pin 64 unused
pin 65 white/yellow pin 5 t10-black brakes *cut*
pin 66 white/red pin 4 t10-white no idea *cut*
pin 67 unused
pin 68 black maf *cut*
pin 69 grey/blue throttle *keep*
pin 70 grey/white throttle *keep*
pin 71 yellow/black map/iat *keep*
pin 72 unused
pin 73 grey/green map/iac *keep*
pin 74 unused
pin 75 unused
pin 76 unused
pin 77 unused
pin 78 unused
pin 79 unused
pin 80 purple/yellow pin 7 t10-white no idea *cut*
pin 81 purple/grey to 2 wire plug
 

CasaEd

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Ok had a quick look at a wiring diagram, and this is the minimum amount of wires I would consider using in your case:-


Pin 1 EC Relay
Pin 2 EC Relay
pin 4 Earth
pin 5 Earth
Pin 12 Accel Pedal
pin 16 OBD plug (K-Line)
pin 18 Engine Control Relay
pin 27 Tacho signal
pin 31 Boost pressure sensor
pin 37 Ignition Switch
pin 40 Glow Plug Light
pin 50 Accel Pedal
pin 51 Accel pedal
pin 52 Intake air temp sensor
pin 62 N75 valve
pin 69 Accel pedal
pin 70 Accel pedal
pin 71 Turbo boost press sensor
pin 73 Intake air temp sensor



In your list you're still planning on taking the N75 valve out. What method do you intend to use to control the turbo boost pressure ?
 

Runninwild

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AAZ swapped 2000 tacoma
Wastegates. I contacted malone they said to keep the n75 as the ecu needs the signal but to just not hook it up. I also got a copy of the bentley ive been comparing my pinout too. Looks like there's a few differences between my harness and my ecu (they arnt from the same car). Off the top of my head the 2nd glowplug wire is different (fixed it) and the other big difference i noticed is all the pins from my t10 blue connector (throttle related) seem to come from a 6 pin black plug according to the bentley? Beyond that some of the pins leading to the other t10 connectors correspond with different locations in the bentley vs my harness. I need to search the bentley to find what those wires actually do but I'm in the process of figuring it all out
 

CasaEd

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I don't have a Bentley manual, the only other black plug i can think of is the original accelerator plug, which is black and 6 pins, what i posted up should get you up and running. which Which ECU are you using ? the 80 pin harness can come from a later VE or PD, VW, SEAT or Audi, it doesn't really matter, you just remove the wires you don't need.
 

Hasenwerk

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1982 Cabriolet (BEW|VNT17|Stage4), 1989 VW TriStar Syncro soon-to-be CR TDI (CBEA), 2001 Ford Ranger Edge 4x4 (ALH|VNT17|R520|Stage4)
There are six different flavours of the ALH harness
1997 to 1999 81 Pin
2000 to 2001 121 Pin with a "two wire" glow plug relay
2002 to 2003 121 Pin with a "four wire" glow plug relay

Each of the three above are also available in manual and automatic. There are wiring differences between these beside the glow plug. So one diagram doesn't suit all.
 

Runninwild

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AAZ swapped 2000 tacoma
I've pretty much got it all figured out and have stripped the harness. The Bentley lists some connectors that didn't really make sense but I have been able to trace each and confirm their function other then a few wires.

can anyone confirm this information for me

pin 24 In Bentley it leads to t10 white pin 10, but I cant find its function. the alh pinout sticky doesn't list anything for it and the other pinout I found lists it as the check engine light?

pin 47 in Bentley leads to t10 white pin 9 cant find the function


pin 66 in Bentley leads to t10 white pin 4 cant find the function, alh sticky has nothing

pin 80 in Bentley leads to t10 white pin 7 cant find function, alh sticky has nothing


Beyond that are all the outputs from the ecu for relays a negative trigger? for example on glowplugs I would just tie the signal wire into a bulb on my cluster (negative trigger)?


i found the cluster pinout for the malfunction indicator light, it looks like this just ties into the k line from the obd2 port. when the ecu detects an error does it just throw a ground on this wire to trigger the bulb or is there a dedicated pin for the mil (pin24)?

I'm also playing with the idea of swapping a golf/jetta cluster into my Tacoma. Does the data display on the cluster use the k line for information or the canbus wires or both?

I'm also thinking of possibly hooking up cruise control. ive identified each wire from the ecu that's necessary but i cant find the function for each wire. it looks like there is a few wires that go into the switch and 1 wire for the button, as well as the vss, clutch and brake wires that would be needed.
 

eddieleephd

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Battle Ground, Wa
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2002 jetta Wagon
Pins 2, 5, 6 are all necessary. 2 is vss vehicle speed sensor. I'm a fan of keeping all the T14-a wires personally.
T10-8 glow plug relay turn on wire which runs to the glow plug relay integrated into the raintray harness.

I would guess you can get rid of a lot of the wires, however, you need to keep the sensors so the ECM can see them.

Sent from my Armor_2 using Tapatalk
 
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