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Missing Data Frame Signal: Troubleshooting Guide

 
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DeathAngel69
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Post04-08-2002, 17:01    Subject: Missing Data Frame Signal: Troubleshooting Guide Quote

Hello.
I have a 120A alternator installed on my 1Z engine. Unfortunately, instead of a DF signal wire, it has a W-terminal. Can I simply apply 12V to the DF cable, or what is required? I think that the 120A alternator should be able to power the glow plug heating system in the water channels regardless of the climate. And since I almost never drive short distances, the generator load shouldn't be a problem anyway? Am I wrong about this??

Can I simply 'recreate' the signal? icon_rolleyes.gif


Translated on 01-08-2026, 10:17.
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ulf
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Post04-08-2002, 23:07    Subject: LiMA Capacity: What You Need to Know Quote

Hi.

I'm not entirely convinced that the 120A LiMa can handle the glow plug heating system in every situation – if that were the case, mine wouldn't switch off during extended idling (I also have a 120A one).

I'm not exactly sure how to reproduce the signal.
However, an internal DF terminal should also be present on your alternator. Perhaps it would suffice to simply connect this terminal and run a wire from it to the DF input of the engine control unit.
Gruß Ulf
_________

MG4 Electric


Translated on 01-08-2026, 10:18.
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DeathAngel69
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Post04-08-2002, 23:28    Subject: Missing Data Frame Signal: Troubleshooting Guide Quote

Sure, you're welcome.
Has anyone ever done this before? Does anyone know where I should start looking?

That's a good start. I'll take the bra apart tomorrow or the day after and see what I find.

Thank you.

DeathAngel69


Translated on 01-08-2026, 10:19.
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ulf
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Post04-08-2002, 23:41    Subject: Find DF Connector: Types & Where to Buy Quote

Hi.

IMO, one of the carbon brushes should always be connected to the regulator on the DF (Differential Frequency) side. The other ("incorrect") brush would then be connected to ground or a constant positive voltage.
Gruß Ulf
_________

MG4 Electric


Translated on 01-08-2026, 10:20.
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DeathAngel69
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Post08-08-2002, 7:37    Subject: Solution Approach: A Practical Guide Quote

Hello again.

Okay, I've checked everything again.

The damn wiring harness (originally purchased for €571). It had a shoddy finish. The second cable wasn't properly connected to the plug. There was absolutely no contact. Now, at least it doesn't show any errors in the control unit anymore. icon_biggrin.gif

It's really sad --> It's an original part, and then there's a manufacturing defect like that. I'm really angry about it.


Translated on 01-08-2026, 10:21.
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ulf
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Post08-08-2002, 17:19    Subject: Premium Quality: The Real Deal? Quote

Hi.

... or did you perhaps get a counterfeit wiring harness (like a Rolex copy) icon_razz.gif?

Here's the translation:

"Another question: Why does your signature say "LLK"? That usually means "Low Pressure Pump," and every TDI, including the 1Z, has it as standard equipment..."
Gruß Ulf
_________

MG4 Electric


Translated on 01-08-2026, 10:23.
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DeathAngel69
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Post08-08-2002, 17:37    Subject: Quality: What Matters Most? Quote

I seriously doubt that's quality. It was placed there because...
I bought a 1992 Passat with a 2-liter automatic transmission engine. Now I've converted everything to TDI. It wasn't really easy, especially since there were hardly any examples to follow and very little information available. But with a lot of luck and the help of many forums and resources, I managed to get it done.
Therefore, I didn't really have a clear idea of what truly belonged and what didn't icon_smile.gif.
That's why I sometimes ask what might seem like 'stupid' questions!

Thank you and have a nice day.


Translated on 01-08-2026, 10:24.
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