hi all,

got 1.2 8v mk2 punto

i keep getting the same problem over and over again...PO115 engine coolant temperature circuit malfunction

i have changed the coolant sensor 3 times twice with euro parts sensor once with dealer part...it seems to work for a while but happens again couple weeks later but tbh i dont think its the sensor think it just on an off when it wants

the coolant temperature dial in the car stops working temperature showing zero...overheat (red light) comes on...fan stays constantly on until engine is turned off and left for 5mins...both coolant hoses are stone cold because fans been on so long...engine management light comes on...then on its own will just start working again :/

whats up...im guessing its the wiring now...do you think if i cut off the old connector plug and solder a new one on it will cure the problem?

cheers
brin

i would check all the wiring first for splits and stuff and then it might be worth soldering a new plug on

Well the signs your giving brin your car is going into Limp Home Mode

No weather its the Sensor itself Failing yet again
Or there is a wiring issue, i'd start at the sensor and start following it back to the ECU (guessing it goes there) and If the Cable is damaged or not

it could be the plug has a poor connection

What happens if you change the sensor back to an old one?
See what happens then - does the fault come back?

Ziggy

it's circuit malfunction so you need to start checking the wiring and ECU connections.

easier said than done...it all goes into a massive loom can only see about 5cm of wire lol i have noticed that the sensor wiring connector plug is rather wet/mucky looking...every other plug on me car when you take it off is spotless so maybe this problem tbh

Brin said:

easier said than done...it all goes into a massive loom can only see about 5cm of wire lol i have noticed that the sensor wiring connector plug is rather wet/mucky looking...every other plug on me car when you take it off is spotless so maybe this problem tbh

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A Poor connection is a good enough reason

if you can push the connectors out one at a time, get some wire wool or wet and dry and clean the rubbish off the connectors

But why is the sensor getting wet - means something is leaking

Ziggy

signal is going open circuit, hence loss of gauge reading and ECU going default and putting fan(s) on. Wiring goes from that sensor into the loom and into the ECU a few inches away...in wiring terms it's an easy one

T14086 said:

signal is going open circuit, hence loss of gauge reading and ECU going default and putting fan(s) on. Wiring goes from that sensor into the loom and into the ECU a few inches away...in wiring terms it's an easy one

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lol il take a look yh i know were the ecu is just looks like a mission with all loom hahah

could it be ECU fault??

also nothings leaking on it as the sensors at the top

Brin said:

lol il take a look yh i know were the ecu is just looks like a mission with all loom hahah

could it be ECU fault??

also nothings leaking on it as the sensors at the top

Click to expand...

It'd be the first time i've heard about it

Unless you've got a lovely Water Logged ECU which has rusted parts up?

I dowt it like, but i'd start Following the wiring Brin, clean the plug up and see what you find

Ziggy