ML always cold need ECU pinout/voltage
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ml320 yr 2000
ML always cold need ECU pinout/voltage
My ML is running between 40-80c. I get a code po115 engine coolant temp circuit. replaced thermostat,sensor,clutchfan,waterpump,auxillary pump(secondhand) yet I get the message. checked voltage output on coolant sensor connection. I read 0.3 volts. Is this normal?
Id like to rule out wiring harness short. So can anyone provide me with the ECU pinout and voltage output of coolant sensor.
Or am I missing something?? Anyone please send me a reply
Id like to rule out wiring harness short. So can anyone provide me with the ECU pinout and voltage output of coolant sensor.
Or am I missing something?? Anyone please send me a reply
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2002 ML 320 & 2006 ML500
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You were the one who asked repeatedly for these test and now I'll be married to this thread until it's done,
.
Have you opened the pdf ECM Connectors? It clearly shows that there are 6 connectors labeled A to F and all the pins are numbered.
.
Have you opened the pdf ECM Connectors? It clearly shows that there are 6 connectors labeled A to F and all the pins are numbered.
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ml320 yr 2000
Sorry Maj. you are the best.. I did have an idea what ill need to do but am not sure if the pins are actually labeled N3/10 . I have not opened it yet. Way back late 1980's usually if they said N3/10 it would mean connector N @pin 3/10. but here connectors are A-F, no N. I will open it this weekend and study it further. hope i get it right. Thanks for your patience.
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N3/10 means the ECM.
The pdf diagram shows the layout of the connectors. You only have to work with conn. E in the first test. Cut the small wire tie, remove the cover and all the wires and pins will be exposed.
Fan out the wires and in relation to the new illustration below, find wires 28E and 29E, making sure that they are the same colors that are supplied in the test.
The pdf diagram shows the layout of the connectors. You only have to work with conn. E in the first test. Cut the small wire tie, remove the cover and all the wires and pins will be exposed.
Fan out the wires and in relation to the new illustration below, find wires 28E and 29E, making sure that they are the same colors that are supplied in the test.
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ml320 yr 2000
News Flash!! My voltmeter reads 0.3v @50-60 c my ohms read 700+/- . Confirmed its not my harness.. i got same reading when tested the connector at sensor side. A verdict of ECU fault is now favorable. Is there any other tests Ill need to do before i pass thisverdict. Damnn im looking @ 500-600$ on this.
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News Flash!! My voltmeter reads 0.3v @50-60 c my ohms read 700+/- . Confirmed its not my harness.. i got same reading when tested the connector at sensor side. A verdict of ECU fault is now favorable. Is there any other tests Ill need to do before i pass thisverdict. Damnn im looking @ 500-600$ on this.
czar, you are not making this easy for me. I can't guess or assume what test you are conducting.
Open the tests again. They are numbered 8.0, 8.1 & 8.2. You must tell me the results of each test.
8.0 @ ? °C -result is what voltage
8.1 @ ? °C -result is what Ω
8.2 @ ? °C -result is what Ω
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Retest when the eng. is completely cold. Remember that 50°C=122°F.
Aside from you being aggravated or discouraged,it is also up to you to complete all three tests.
Aside from you being aggravated or discouraged,it is also up to you to complete all three tests.
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ml320 yr 2000
finally did a retest..engine cold cali weather@ 66c... test 1 key @ on position voltage reading at 0.4v test 2 engine key off reading 3000+ohms test 3 3000+ ohm. Can i just buy a used ecu same model and slap it in there? Now im confirmed a sad person with a sick ecu
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Secondly, ohm readings are testing the wires, not the ECU. You do not need and ECU.
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ml320 yr 2000
That's correct. With my engine cold. I should be at least be getting 3v. But I am getting a 0.4v. This is a voltage of a hot engine. My obd2 scanner reads -40c. But that reads off the temp sensor voltage feedback..which is questionable due to my suspected ecu voltage supply inaccuracy. So with engine cold. Not cranked at all. First thing in the morning after overnight park In Garage . These were my readings. Ohm reads consistent . If it's not ecu, what else could it be?
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If you want to replace the ECU go right ahead and do so. Just match the number on it.
Just to check how you made the voltage test. I don't know what type of meter you have, digital, auto ranging, but I hope you had it on the correct scale.
You originally said that you got a 0.3v, if you didn't have it on the correct setting, that could mean it is actually 3.0v
Just to check how you made the voltage test. I don't know what type of meter you have, digital, auto ranging, but I hope you had it on the correct scale.
You originally said that you got a 0.3v, if you didn't have it on the correct setting, that could mean it is actually 3.0v
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It's supposed to be set on the 12v scale, but how you conducted the test I do not know. You have to make sure that you have the correct wire colors in the correct position.
