fault code p0544 - Turbo Upstream temperature sensor

[antonioballoni]

Hi,
I currently have a Kangoo 1.5 cdi ,2008, engine k9k 806, it runs pretty well.
A few weeks ago the check injection system light came up. I plugged in an ODB reader and it showed code P0544(pending).
It had been intermittent for a couple of weeks till it turned into a confirmed error code.
Now the light doesn't come up anymore, but the ODB reader says it's still a confirmed error.
I believe the ECU is trying to extablish if the fault is gone for good before clearing the error code.
The strange thing is that the sensor is still the same, I never replaced it.
So I took out my multimeter to check the sensor and it reads a resistance grater than 2MΩ (the upper limit of my multimiter) when cold,
and around 30KΩ when hot.
Does anyone know what readings I shoud get from a working sensor?

Many thanks
Antonio

[NewcastleFalcon]

If what you are talking about is an exhaust gas temperature sensor, cant imagine they are much different across different makes of vehicle.

I replaced an EGT Sensor on A Vauxhall Vectra Cdti 1.9 Fiat derived engine and the ohms reading out the box of the new EGT sensor was 220 ohms. The car had an upstream one and a downstream one. one of the sensors on the car was around 220 ohms (Upstream one) while the faulty downstream sensor was in the off the scale territory.

These were simple two wire sensors and the resistance measured across the wires at normal ambient temperature.

I would do your multimetering again on the low ohms scale to catch a value around 220 ohms, which if its anything like the EGT sensor I did, is a rough guide to the normal resistance of an EGT sensor.

Best I can offer from my experience which isn't with your engine, or a Renault Kangoo. Others with more knowledge may be along to assist, and provide a better guide than me.

Good Luck

Regards Neil

[antonioballoni]

Neil, thank you for your reply.
Yes, I was talking about the EGT.
I believe my sensor is a NTC type, the higher the temperature the lower the resistance.
I tested it on a gas stove and it behaves accordingly.
The readings were repeatable and consistent, but I'm still in doubt about the range of values.
I found on the web a reference range of 1.1MOhms - 140KOhms but it's for a Megane (with the same engine),
and it's the only reference I've found...besides it's not that different from my readings...
So I'm still looking for 100% certain reference data.

[antonioballoni]

I think my sensor works as the one on the right, while the one you were talking about as the one on the left.

[antonioballoni]

Update:
this morning I watched an interesting video on NTK web site (my sensor is from NTK),
and near the end it showed what the resistance at room temperature shold be: around 6MOhms.
It also gave me a plot of T vs Resistance !! Now I think my sensor is not faulty, that saved me around 60 pounds.

[NewcastleFalcon]

Update:
this morning I watched an interesting video on NTK web site (my sensor is from NTK),
and near the end it showed what the resistance at room temperature shold be: around 6MOhms.
It also gave me a plot of T vs Resistance !! Now I think my sensor is not faulty, that saved me around 60 pounds.

Pleased to hear it Antonio. At least the chart you put up for the type of sensor I had, confirmed pretty much what I recalled from changing mine on another type of car.

You clearly have good knowledge.

Regards Neil

[antonioballoni]

Thank you Neil, you are too generous.
I'm happy the sensor is working fine, of course this also means I have to look a little deeper into my problem....

Regards Antonio