Alex Crow
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with warm engine expect zero voltage.
Yes, I would spend a little time checking. Check also for short circuits between the wires - insulation failure is a possibility. I don't know if the ELR controller is robust against short circuits, but, if not, a short could take out any new ELR controller you might fit.
Absolutely, I don't want to get sloppy - not sure, but looks to me like a diode in the diagram so worth being careful!
That the tacho is working suggests that the ELR control unit is getting power, and is, fundamentally, working.
well it seems to be getting all the signals it should, now - crank sensor and 12V from the OVP tested ok now, temp sensor - tested ok at the sensor itself, will test from the ELR socket to be sure!
For the sake of completeness, and before spending serious money, I would also spend a little time making sure that the coolant temperature signal, as seen by the ELR controller, is correct.
Connect a pair of wires to the ELR solenoid and just touch the +12v post for a second. The solenoid will react instantly if it's good.
Problem now - not sure how to read the manual when it says -
'engine idling - unplug coupling at actuator, measure Voltage = 12V'
I get 0V across the two terminals , but 13V between red/blue terminal and earth (and 12 without engine running..) not sure what they mean here?
Think I need another look...
..........BUT - at 20C it should be 2.2 - 2.8 kOhm - I only get 900 Ohm! Well short, according to the spec sheet equal to 50 C, nowhere near 'cold start temps?
Would that be enough to throw the ELR off?
Not ideal, but, I can't imagine those resistance readings preventing the system working at all - it isn't as though the readings are completely outside the allowable range of values - it's neither a short or open circuit.
Does the idle stop screw show signs of having being messed with?
there IS a problem! can you be 100% sure about those values? if so you have a hot suspect - air temp here today is +25 degC btw.
Which is correct because the return line goes open circuit when the solenoid is not operating.Earthing the signal wire with the ELR out upped the tickover so that wiring is ok, but the Voltage was only about 0.1V with it back in?
Which is correct because the return line goes open circuit when the solenoid is not operating.
I suspect not as the ELR is meant to be in use all the time for idle stabilisation, is it not?So the next question is - does the wrong reading from the coolant temp sensor explain no output from the ELR....all the other inputs seem to be right...
I suspect not as the ELR is meant to be in use all the time for idle stabilisation, is it not?