D24 - Can't solve temperature problem

[Maciek4530]

Originally Posted by ngoma

I don't know if the diesel versions of the temperature sensor and gauge are different from the gasser versions but there was some extra circuitry involved in the model years of your samples that tampered with the "true" readings that artificially kept the needle in the middle.

This is why I wanted you to take readings with an IR thermometer, so you could easily verify actual temperatures. Can you borrow one? You could read the temperature of the temperature sensor itself and compare it to the gauge.

"1986-1993 240 models are equipped with circuitry that is designed to keep the coolant temp gauge needle positioned in the normal zone (9:00 position) even if the engine is running a bit hot. The idea is to prevent minor variations in coolant temp from causing worry for the driver. As these cars age a common problem is the failure of the circuit board and connectors resulting in erratic readings or no reading at all. We have put together a simple bypass harness that reverts the function back to the earlier trouble-free design."

From
https://www.ipdusa.com/products/5670...-Volvo-1363117

More info:
https://cleanflametrap.com/tempFaker.html

https://www.youtube.com/watch?v=0AL4hphLMnE

Yep, but that is about US versions

In Europe we don't have system like this (and we happy abut that ) - we know exacly about all small changes in water temperature basis on gauge.

I try to borrowe IR thermometer