1999 2.5TD (YD25) - No charge from alternator + Water in Fuel light warning on!! Bad voltage signal from warning lights circuit?

[burrch]

Hi

Short Story :

No charge to battery
Alternator warning light on
Water in Fuel warning light permanently on (even when unplugging sensor)
Alternator Loom connectors look good - no corrosion / visible damage
Battery 12.7 volts at rest / 11.97 with engine running
Alternator signal feed wire (yellow / black) = 1.9v

Whats next - trace for broken alternator signal wire???

Long Story

First post , for my first Nissan... Just bought it, thinking probs needed a new alternator or reg/rec etc .. had a look online and probs not so simple! Optimism trumps experience and good judgement (again...)

I found a few posts on here with similar story , multiple warning lights + no charge from alternator , cause being that signal voltage needed to trigger the alternator to charge coming from same circuit as the dashboard warning lights, hence the faulty warning lights behaviour.

Thought I would tackle the Water in Fuel warning first , after pointlessly draining the (recent looking) fuel filter , and realising that unplugging the fuel / water sensor should make the warning light turn off... brought me here!

Any tips on how to trace the fault?

tested so far:
Fuel Water sensor is good - also tried disconnected
Battery to Alternator voltage good (battery volts same as the volts on the big cable to nut on Alternator)
Battery to Alternator Loom - engine running :
Yellow / Black - 1.9v
Yellow / Red - 11.9v ...

Ran out of light / brains pretty quick, so any advice appreciated !! The Mrs is pissed at buying another truck ... this aint helping win her over haha

 

[Ben Juett]

Hi

Short Story :

No charge to battery
Alternator warning light on
Water in Fuel warning light permanently on (even when unplugging sensor)
Alternator Loom connectors look good - no corrosion / visible damage
Battery 12.7 volts at rest / 11.97 with engine running
Alternator signal feed wire (yellow / black) = 1.9v

Whats next - trace for broken alternator signal wire???

Long Story

First post , for my first Nissan... Just bought it, thinking probs needed a new alternator or reg/rec etc .. had a look online and probs not so simple! Optimism trumps experience and good judgement (again...)

I found a few posts on here with similar story , multiple warning lights + no charge from alternator , cause being that signal voltage needed to trigger the alternator to charge coming from same circuit as the dashboard warning lights, hence the faulty warning lights behaviour.

Thought I would tackle the Water in Fuel warning first , after pointlessly draining the (recent looking) fuel filter , and realising that unplugging the fuel / water sensor should make the warning light turn off... brought me here!

Any tips on how to trace the fault?

tested so far:
Fuel Water sensor is good - also tried disconnected
Battery to Alternator voltage good (battery volts same as the volts on the big cable to nut on Alternator)
Battery to Alternator Loom - engine running :
Yellow / Black - 1.9v
Yellow / Red - 11.9v ...

Ran out of light / brains pretty quick, so any advice appreciated !! The Mrs is pissed at buying another truck ... this aint helping win her over haha

Hi

Just wondering if you managed to work out why the water in fuel light remainder illuminated. My D23 is doing the same thing even when unplugged. It started off being an intermittent fault but now remains on continuously.

Cheers