Help! VW T4 2.5 diesel engine temp light flashing...

[r4dent]

" stopped & found water & oil levels are def ok.

1) Did he check the coolant level. There is no water level, but he may have checked screen wash.

If this is the light that flashes it is a coolant level light as well as an engine temp light.
Light flashes when coolant too high or too low.

Red Engine Coolant Fault Warning Light | Volkswagen UK

Find out what the red engine coolant fault warning light means and what actions to take. Learn about van warning lights at Volkswagen UK today.

www.volkswagen.co.uk

2) Does the light come on when you switch on with a cold engine

3) What did the engine temperature gauge read?

4) This is worth a read as well. https://www.fixter.co.uk/blog/reasons-your-engine-temperature-warning-light-might-illuminate/#:~:text=Hot Weather,engine temperature light turns on.

5) If all else fails. https://www.volkswagen.co.uk/en/fin...t-app=51.50478&lng-app=-0.1371730&zoom-app=10

 

[mariesnowgoose]

Val54 has just posted this over on motorhomer:-

"It should look something like this ..........

Radiator Fan Thermo Switch Fits VW Transporter T4 1990-2003 701 959 481 | eBay​

I think your pic shows the sensor for the glowplugs."

Neil sent me this pic of the above unplugged not so long ago.

Is he looking at the glow plus sensor then and not the radiator fan thermoswitch?

He does have the vehicle manual that came with the camper which he has referenced, but not being there myself I've no idea if it shows the relevant engine parts or not?

 

[mariesnowgoose]

1) Did he check the coolant level. There is no water level, but he may have checked screen wash.

If this is the light that flashes it is a coolant level light as well as an engine temp light.
Light flashes when coolant too high or too low.

Red Engine Coolant Fault Warning Light | Volkswagen UK

Find out what the red engine coolant fault warning light means and what actions to take. Learn about van warning lights at Volkswagen UK today.

www.volkswagen.co.uk

2) Does the light come on when you switch on with a cold engine

3) What did the engine temperature gauge read?

4) This is worth a read as well. https://www.fixter.co.uk/blog/reasons-your-engine-temperature-warning-light-might-illuminate/#:~:text=Hot Weather,engine temperature light turns on.

Thank you very much for that

I texted Neil to ask if the engine was really hot when he first stopped and opened the bonnet.

He didn't answer that question specifically, but replied that the temperature light was flashing and the temp gauge was on max, plus the fans weren't moving after an hour of driving?

 

[mariesnowgoose]

Erm... Neil just sent a text to say that when he shorts it out the fans start up...?!

Definitely not the glowplug sensor then

 

[NeilyG]

How to change the radiator fan switch on a VW T4 Transporter

A guide on how to change the fan switch on a Volkswagen T4 Transporter.

vanlife.tv

T4 Radiator Fan Switch

Replacement thermostat switch which is used to turn the radiator fan on and off at the correct temperatures.For use on

www.coolairvw.co.uk

Yeah, saw that. Looks like I will have to be quick on the draw to avoid too much coolant coming out.

The part looks right - with 3 prongs.

 

[NeilyG]

Neil sent me this pic of the above unplugged not so long ago.

Is he looking at the glow plus sensor then and not the radiator fan thermoswitch?

He does have the vehicle manual that came with the camper which he has referenced, but not being there myself I've no idea if it shows the relevant engine parts or not?

View attachment 135727

There’s a Haynes manual but it’s for the T5 - for whatever reason.

Must surely be the thermoswitch if shorting it starts up the fans?

 

[r4dent]

Thank you very much for that

I texted Neil to ask if the engine was really hot when he first stopped and opened the bonnet.

He didn't answer that question specifically, but replied that the temperature light was flashing and the temp gauge was on max, plus the fans weren't moving after an hour of driving?

Plan A - Replace the fan switch

Plan B - Get recovered home

Plan C - Short out the switch to get home This will mean the fan is always running.

Plan D - Drive home, stopping for 30 mins the moment the temp gauge goes above normal.

 

[The laird]

Fan transmitter switch defo ,bridge it out and the fans will run all the time and overcool so you can get home ,mind the big brass washer when switch is removed to renew don't think you get a new washer with new switch marie

 

[RichardHelen262]

There’s a Haynes manual but it’s for the T5 - for whatever reason.

Must surely be the thermoswitch if shorting it starts up the fans?

If shorting the switch brings the fans on then you are correct it just needs a thermoswitch,

 

[Pudsey Bear]

I was fust wi me bit of wire nah nah nah nah nah

 

[mariesnowgoose]

I was fust wi me bit of wire nah nah nah nah nah

You were so

 

[wildebus]

If shorting the switch brings the fans on then you are correct it just needs a thermoswitch,

oddly enough, the more common problem is not the fan NOT coming on, but the fan staying on Same fix however