Renault Megane Coupe - Coolant heater

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Thu 12 Oct 2023 17:11
Renault Megane Coupe - Coolant heater - mcb100
2012 Megane Coupé 1.6dci with an intermittent EML. I’ve had it plugged into a Renault diagnostic laptop which is flagging up ‘secondary coolant heater’, but I’m not convinced it has one.
Has anyone got access to a wiring diagram for the car? The Haynes manual doesn’t cover this engine.

Edited by mcb100 on 12/10/2023 at 17:11

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Thu 12 Oct 2023 17:37
Renault Megane Coupe - Coolant heater - elekie&a/c doctor
If you take a look in the engine, there should be an aluminium housing in the cooling system that has 3 or 4 heating plungers screwed into it with some push on electrical connectors. If one or more are faulty, then the complete assembly needs to be replaced. The device is to increase the coolant temperature from cold .
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Thu 12 Oct 2023 18:00
Renault Megane Coupe - Coolant heater - mcb100
Thanks.
That’s how I’ve had it described to me previously. I can’t see it from the top, looking down, so I’m assuming it’s under tray off and look up.
Job for a garage next week before an MOT the week after.

Edited by mcb100 on 12/10/2023 at 18:01

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Wed 18 Oct 2023 14:21
Renault Megane Coupe - Coolant heater - mcb100
And the part’s on back order…
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Wed 25 Oct 2023 20:13
Renault Megane Coupe - Coolant heater - mcb100
‘Thermoplunger’, as it’s apparently known is now replaced and EML is out.
No wonder I couldn’t see it from above, it was in front of the n/s/f wheel behind the wheel arch liner.
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Wed 25 Oct 2023 20:19
Renault Megane Coupe - Coolant heater - elekie&a/c doctor
Well done. You probably could have not bothered replacing . It’s not a major player in the engine management system. It’s there to help warm up the coolant. At least it’s put out the mil .
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Fri 27 Oct 2023 06:42
Renault Megane Coupe - Coolant heater - mcb100
Yes, slightly frustrating that it’s driving exactly the same as it did previously, taking the same amount of time to warm up, but needed a £215 part to extinguish an amber light that would have prevented it getting an MOT.
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