P26F700 - Coolant Pump "C" Supply Voltage Circuit

[mfizz]

Had the engine light pop up on my 2016 superb CRLB.

 

P26F700 - Coolant Pump "C" Supply Voltage Circuit

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Can someone tell me which pump this is? Is this a common fault? Should I be checking other things?

 

[mfizz]

Could do with some assistance please. I am sure others have had this issue. I just want to see what I should be trying before the obvious replace the entire pump.

[Breezy_Pete]

From what I can see here: Passat B8 1.6 Coolant Pump C P26F700 Supply Voltage Circuit error | UK Volkswagen Forum the pump in question is known as V488 in the circuit diagrams, which on your car is supplied by fuse 7 in the engine bay fusebox, a 10 amp fuse.

If that is intact, check the power and ground are getting to the connector (see @Crasher's image in linked thread) of the pump.  Pin 1, a brown wire should connect to earth/battery negative;

pin 2 a red/blue wire should have 12V when engine is running;

pin 3 green/yellow wire is the control signal from engine ECU pin 37 on the 91-way connector.

These all go via an intermediate 10-way connector pair somewhere on nearside (UK) of engine bay, through pin numbers 7, 8, 9. So find that and check for wire damage nearby, as well as near the pump itself.

 

Edited 26 May, 2023 by Breezy_Pete
typo

[mfizz]

Thank you for your response. I checked the fuses and they had continuity and they were fine. Did swap with another 10a just to be sure.

 

Next step will be get under the car to have a look and trace the wire. I have a feeling that the pump itself is gone. When I turned the car off the other day I heard a "glug glug" sound almost as if the the pump was trying to turn on. Idea of getting under the car is so daunting now.

 

Will feedback on the progress.

[Jonnyhammond]

Hi mfizz did you get issue sorted I'm having same issue

[mfizz]

I have just left it as is for now. I will replace the pump eventually. But I don't think it's causing any damage given how cold it is right now and I don't use the rest function.

 

Unless someone thinks different?

[mfizz]

I am revisiting this because I'm finally going to change the pump. I thought that both v488 and v188 were the same. 

 

Upon inspection of the part the front pump (v188) is definitely the Bosch 965 567

 

The back pump v488 (pump c which is the issue) doesn't look like the same one in the front. I don't want to dismantle the whole thing to check. But is it possible the front one is Bosch and the rear one is Pieburg? From reading posts on others forums, mainly @Crasher on the issue I thought they were the same part number.

[mfizz]

I can't believe it, turns it out the back pump is a 5q0 965 561 b and the front one is a Bosch 2q0 965 567.