P0C73 Coolant Pump Error

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Might want to review that wiring diagram for the coolant pump before getting too wild with applying power to signal control lines with no current regulation or fuse.

How will you measure the speed?

What will it mean if the pump seems to run? (but no speed measurement)

what if it doesn't run? (without knowing if the wiring or power sequence is correct)
Thanks kiev,
I did try applying power directly to the pump socket, unfortunately with nil result.
12v +ve to pin 3 Vbatt
12 -ve to pin 4 eth
12v =ve to pin 1 (wp) Vbatt
also measured voltages on plug
with key to Aux position
12v pin 3
with key to On position
14v pin 3
so appears as if Volts are at least getting to the pump plug ie relays and fuse ok.
also measured DC resistance of pump coil pin 3 to pin 1 930 ohms.

So my conclusion : Pump is "kaput" !

However philsuth was talking about testing his old pump in a bucket and it would be interesting to
know if he can power up his pump using the same method as I. (before I pull mine out).
How about it phil ?

Have looked at new pumps, some available from Japan and also from USofA (at a cost $$$$s)

Thought bubble .... 12v bilge pump as a temp measure ... hand operated ...... ha !



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Another thought :
Here in Aus we have Mitsubshi PHEV (Plug In Hybrids) using the 10.5kw iMiev battery, I wonder how they keep the OBC cool when charging ?
Any PHEV experts out there ??


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It looks almost like the same pump is used on the PHEV ? Not that it helps lower the price.

From a few pictures on the phev forum it appears that they use the same looking OBC, but i haven't seen the insides of one yet to say for sure. But it is likely to be cooled in a similar manners--with a coolant flow to chill an internal heat sink plate.

With power and ground on the correct pins, then the speed might be controlled with a variable voltage on the WP terminal. [ref the control diagram above]

If you are up for more experiments--
Does any voltage appear at the WP terminal when the power and ground are applied? Maybe pulling WP down with a 1k resistor to ground would turn ON the pump? The FSM says to not run it without fluid, probably damage to internal seals.
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Thankyou All,

I have left the pump on the car and ordered a new one, probably a month before it arrives, will resume the conversation then.
In the meantime I have learnt a 'lot' but probably just a 'little' about how the little car works ..... interesting exercise.

I must have upset the "pump GODS" my pool pump is making some strange noises ..... next task ....

An aside new pool pump <$400AUD delivered new cooling pump >$500AUD delivered

Happy days