ALH TDI pinout.

gmenounos

Vendor
Joined
Jun 26, 2003
Location
Watertown, MA, USA
TDI
'99.5 Golf GLS, '01 Jetta GLX Wagon (TDI conversion)
Hey everyone, I'm in the middle of swapping an '00 ALH/5 speed into an '03 1.8t/automatic (both were jetta's).

I'm having trouble with the T14a connector that the pin out is shown on this thread. In the 1.8t jetta, I'm missing pin 3 (green) and pin 10 (black with green stripe).

I also see on the diagram that pin 10 should go to the load reduction relay. I traced this black/green stripe wire to fuse 10 (small fuses) on the 2000 wiring, but it doesn't seem to exist on the 1.8t. The bottom blade of the load reduction relay traces continuity to fuses 20, 21, and 36 on the 1.8t, but those also exist on the TDI, so I need that extra wire...
Pin 88 of the ECU goes to pin 10 of T14a which then goes through a 5A fuse to the fat black wire with red stripe that goes to the load reduction relay. Your 1.8t jetta will not have that 5A fuse so you'll need to add it. You could probably just add an inline fuse - that's what I did to make my glow plugs work on my ALH conversion.
 

oldpoopie

Vendor
Joined
May 14, 2001
Location
Portland Oregon
TDI
2001 golf gl, 2006 jetta, 1981 ALH swapped rabbit pickup, 1998 beetle
Nice. Havent looked at those in like 8 years. Glad you saved them from photobucket jail. Lol
 

Saburai

Member
Joined
Nov 15, 2020
Location
32696
TDI
1998 Jetta
What a great resource! I'm doing a AHU/Tracker swap. Does anything like this happen to be available for the AHU?
 

ken.fresno-tdi

Veteran Member
Joined
Jan 3, 2006
Location
Fresno, CA
TDI
95 Eurovan EVC camper with 98 AHU engine (VeganVan02); 01 Jetta ALH engine and parts - waiting for transplant into 97 Eurovan (VeganVan03);05 BEW Beetle
Here you go.... most everything is there.... This is from a 98 Jetta. Earlier ones are almost identical.

Pin# Colour Function

1
Brown Ground

2 Black/Green Glow Plug Light

3 Not Used

4 Brown/Yellow Quantity Adjuster Pin 6

5 Brown/Yellow Quantity Adjuster Pin 6

6 Black/blue Coolant Glow Plug Relay Single

7 Gray/Green Modulating Piston G149-2

8 White Engine Speed Sensor G28-2

9 Not Used

10 Not Used

11 Blue Needle Lift Sensor G80-2

12 Gray Needle Lift Sensor G80-1

13 Brown/Red Mass Air Flow Sensor Pin 6

14 Blue/Brown Coolant Temperature Sensor G27-1

15 White/Blue Throttle Position Sensor Pin 1

16
Blue/White Oil Pressure .3 Bar F22

17 White/Red Clutch Switch F36-2

18
Yellow/Red ?

19 Red/Green Mass Air Flow Sensor Pin 1

20 White/Yellow Brake Light Switch F47-1

21
Not Used

22 Not Used

23 Black/Yellow Switched B+ from Relay 109 output

24 Brown Ground

25 Brown/White Exhaust Gas Recirculator Valve N18-2

26 Black/Brown Coolant Glow Plug Relay Dual

27 Not Used

28 Brown/Green Air Conditioning Relay

29
Violet/Black Modulating Piston G149-1

30 Green/White Glow Plug Relay J66 Pin 7

31 Blue/Yellow ?

32 Gray ?

33 Brown/Blue Sensor Ground

34 Blue/Gray Cruise Switch E45-2 Resume

35 Red Cruise Switch E45-3 Set

36
Not Used

37 Green/Gray Air Conditioning On (Signal from AC system)

38
Black Ignition from Key switch

39 Red/Black Alternator Load Signal DF Pin 2

40 Not Used

41 Not Used

42 Black/Violet Power Relay J317 (109)

43 Blue/White Vehicle Speed Signal Cluster Pin 7

44
Black/Red Brake Light F2

45
Black/Yellow Switched B+ from Relay 109 output

46 Brown Ground

47 Red/Blue Wastegate Control Valve N75-2

48 Blue/Green

49 Brown/Yellow Quantity Adjuster Pin 6

50 Yellow/Blue Glow Plug Relay Pin 1

51 Brown/Black Cold Start Injector N108-2

52 White/Green Modulating Piston G149-3

53 White/Black Fuel Cutoff N109

54 Not Used

55 Green/Red Throttle Position Sensor Pin 3

56
Not Used

57 Green/Yellow Throttle Position Sensor Pin 2

58
Not Used

59 Blue/Black ?

60 Yellow/White Malfunction Indicator Light

61 Gray/White On Board Diagnostics Connector Pin 7

62
Green/White Throttle Position Sensor Pin 5

63
Yellow/Black Fuel Temperature Sensor G81-1

64 Blue/Yellow Intake Air Temperature Sensor G81-1

65 Green/Blue Throttle Position Sensor Pin 4

66
Black/White Cruise Switch E45-4 On

67
Not Used

68 Black/Yellow Switched B+ from Relay 109 output
 

Saburai

Member
Joined
Nov 15, 2020
Location
32696
TDI
1998 Jetta
Thanks! Pardon my ignorance, but this is the pin out for the ecu connector, correct? Many thanks!
 

ken.fresno-tdi

Veteran Member
Joined
Jan 3, 2006
Location
Fresno, CA
TDI
95 Eurovan EVC camper with 98 AHU engine (VeganVan02); 01 Jetta ALH engine and parts - waiting for transplant into 97 Eurovan (VeganVan03);05 BEW Beetle
yep. It has a 68 pin ECU. Best way to do a TDI conversion with one is to make sure you get the engine wiring harness, the go 'gas' pedal, brake and clutch pedal switches, and a good engine.
 

94cobra2615

Veteran Member
Joined
Jun 16, 2013
Location
ohio
TDI
2002 Black Wagon
Is there a way to increase the resolution of the pinout diagrams? I can barely read them
 

ken.fresno-tdi

Veteran Member
Joined
Jan 3, 2006
Location
Fresno, CA
TDI
95 Eurovan EVC camper with 98 AHU engine (VeganVan02); 01 Jetta ALH engine and parts - waiting for transplant into 97 Eurovan (VeganVan03);05 BEW Beetle
If you right click on the image, copy it, then paste it into a program like Word it will show up as a picture. It is then much more clear.
 

alvaropach

Member
Joined
Jan 19, 2021
Location
venezuela
TDI
1.9 alh
hi i have a jetta mk4 2005 1.8t and try to swap alh 1.9 tdi , now we have a lot of pronblem whit wiring harness see the pin out and is a good beguinin , i have 3 dtc codes but no have diesel presasure in the injectors
dtc are
17660
19561
17970

if you can help me many thanks
 

alvaropach

Member
Joined
Jan 19, 2021
Location
venezuela
TDI
1.9 alh
These pictures are subject to change but I wanted to get the information I have gathered out there. I know there are plenty of people that do TDI swaps beyond just VW people. My goal here is to help ALL TDI swappers get there swaps running as the factory intended.

Please remember though...my donor is from a 2001 Beetle Auto donor and going in a 1984 Rabbit GTI so I'm a little geared toward that thinking.

This is also an evolving set of picture. I haven't even finished the swap yet but I'm close to having the wiring figured out.

And now I present...

ALH TDI wiring Version 1.2

1.1 - change - correct title
1.2 - change - T6/1 Brown - power to ECU when key is on. To pin 121/37 on ECU.



hi dear i need your support make a swap om jetta mk4 1.8 t to 1.9 tdi alh ngine of gof mk4 2001 , i make work but no have power the turbo run 17 lbs but no chamge the aceleration when beguin to load boost , check all an i dont know what more to do i think is a signal missin but check all wiring and go to the ecu
 

tgray

Veteran Member
Joined
Sep 12, 2004
Location
Marengo, IL
TDI
'02 Beetle, '05 Golf, 2000 Jetta, 2001 Jetta, 2002 Jetta
1st make sure your turbo is working right. Hook a vacuum hose with full vacuum to the turbo while idling. You should see the actuator move fully while putting the hose on and off. You should hear a different sound. If that is working then take a good look at where your hoses are connected. Make sure you have everything mechanically right before you look at the electrical side. Make sure the right plug is in the right module. The EGR valve looks just like the turbo.
 

Timpo456

New member
Joined
Apr 18, 2020
Location
The netherlands
TDI
lupo 3l 1.2tdi
so I'm doing an engine swap do you need to hook up pin 88 to anything or not? like I'm confused what pin I need to power up the ecu. like ignition on. I know I need to hook up pin 1 and 2 to 12v power and 4 and 5 to ground pin 3 is empty rest goes to the colored plugs, Map sensor and to starter and I guess speed sensor?
 

gmenounos

Vendor
Joined
Jun 26, 2003
Location
Watertown, MA, USA
TDI
'99.5 Golf GLS, '01 Jetta GLX Wagon (TDI conversion)
so I'm doing an engine swap do you need to hook up pin 88 to anything or not?
Yes, if you want your glow plugs to work:
 

ccorn90

Member
Joined
Dec 30, 2023
Location
Seattle, WA
TDI
'03 Jetta ALH, '00 Golf ALH
Hi folks, wondering if anybody can do a back-check for me on the following. Wanting to make sure I have the protocols right - the key question being whether 5V or 12V is the expected VSS. For the rest of them, I'm pretty sure I have it right but any and all input would be appreciated!


 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
As you may know, the circuit from ECU Pin 20 goes to the Cluster at T32/3.

So, I am not sure what you are trying to determine. If it is 5 volts or 12 volts, you cannot change it. Other than tapping into that circuit, I have no clue how you could determine the voltage.

Anyway, when I installed the ALH TDI engine in my Vanagon, I tried to incorporate as many of the bells and whistles as possible. For example, I modified the Jetta Cluster to fit in place of the Vanagon Cluster.

In reference to the VSS in my Vanagon application: I screwed the VSS head onto the Ticker Box of the Vanagon (perfect fit) to obtain wheel rotation input. The VSS gets 12 volts from Fuse #7, per the schematics. The VSS output signal (no clue the voltage) goes to the Input on a Dakota Digital Interface that I used. I used Switched 12 volts to the Dakota Digital Interface. Most likely with advice from someone who knew, I chose the 2000 ppm Output signal to the Cluster at T32/28. The Dakota Digital Interface has Up and Down dip switches to calibrate the signal going to the Cluster. With the help of my wife, we drove down the highway using GPS to let me know how fast the Van was moving. We set the speed spot-on. Luckily, the odometer is about 99.99% accurate.

So, I surmise once the Cluster receives the signal from the VSS (in my case, the Dakota Digital) it uses it to operate the Speedometer. And, at the same instant the signal goes out 32/3 of the Cluster to the ECU at Pin T120/20. The ECU uses the data to operate the Cruise Control.

I know this doesn't directly answer you question. Maybe someone that's monitored the voltage or have a known source of info can provide the answer you seek.
 

ccorn90

Member
Joined
Dec 30, 2023
Location
Seattle, WA
TDI
'03 Jetta ALH, '00 Golf ALH
Thanks for the reply @AndyBees.

What I'm trying to determine is whether I can tie pin 20 directly to an 12V, 8000 pulse-per-mile signal that's existing in the swap vehicle, or whether I will need to use a level shifter to match the signal that the ALH ECU is expecting already.

Since the donor car is trash, I don't have an easy way to sniff that signal and see what's going on. If anybody has info on this, that would be really appreciated!
 
Top