Engine temperature (Dashboard)

[Johann]

I'm using a LinkPlus G2 in my Volvo 850 5 cylinder. The factory management system used to be a Bosch LH 3.2/EZ 129K system. The engine temperature is measured by the management and converted to a modulated frequency signal to drive the temperature gauge in the Yazaki or VDO dash. Is there a way to replicate this setup with the linkplus G2 so I can use the temperature gauge in the factory dash?

[ashesman]

I havn't tried this, but here is one way I can think of.  If you are not using boost control, wire an aux output to your temp gauge and select it as open loop boost control.  Set all the duty cycle values across the RPM range to 50%.  Turn on ECT Boost trim.  Use the ECT boost trim table to trim the duty cycle as required to calibrate the temperature gauge.  Like I said, I havn't tried this.  You will also need to set the PWM frequency correctly and check that the signal on the pin is generating a nice switching signal.

[Johann]

Does the new firmware 1.7 change anything for this? Concerning both the Linkplus G2 and Linkplus G3 btw... And, although late, thanks for the reply. Unfortunately I didn't test the mentioned setup yet...

[Johann]

17Hz is high temp (Max) 18-19 Hz is 3/4 high 20-23 Hz = middle = target 23-30 Hz steps to minimum temp. Doesn't respond to DC settings.

[ashesman]

So it is a variable frequency signal, not variable pulse width.  There is no setting in the ECU (in current or older firmware versions) that will generate this output.  Contact VDO and see if they have a temperature transducer that you can fit and wire to the dash.

[Johann]

I was afraid fro a reply like that.. But thanks anyway!