Well as part of my adventures in investigating and trying to fix a number of other problems, I have my plenum off and I'm in the middle of re-wiring the engine loom to replace my injector and coilpack connectors. While I have the plenum off I have decided to test my IACV-AAC valves as I've always had a suspicion that it had stopped working properly. Running through the various Tech articles abound I have pulled it off and attempted to check it's operation and here is what I have found and can't quite work out. The solenoid itself seems to be free from sticking and any obvious mechanical problems and the resistance of the coil is about what the Tech articles have suggested is normal. I thererfore don't think there is anything wrong with the solenoid itself. Plugging just the solenoid into the wiring loom and plugging in nissan data scan to try and get the solenoid to operate gives nothing....no sound no movement...nothing. pluggin in a multimeter gives odd results but no matter what I set the value to in NDS the reading doesn't change. I'm reading a roughly 200Hz signal with an AC voltage reading of about 0.647V or a DC reading of about 10v. My query is thus multipart... Can anyone confirm that playing with the IACV values in NDS or other consult app while the car is NOT started but with the ignition on...makes the solenoid do something? Has anyone found a way to test the IACV signals coming from the ECU? what readings should I be getting? Are there any know issues with versions of NDS that might mean it's not actually changing the IACV value? What phase of the moon, sun, mars and the stars do I need to wait for before this damn car will run like it should? An increasingly frustrated AB
Just touch 12v to the solonoid and it should click if it's working. Don't worry about resistance and all the other PITA ways of checking.
Thanks Andy but as I said I don't think it's the solenoid itself that is the problem but rather the wiring loom or the signal from the ECU. looking for a way to test that or the system as a whole. AB
Just do a continuity check between the AAC connector plug and the corresponding ECU pinout. The other will go to a 12V ignition source as per most of the zed solenoids. 12V provided to one pin of the AAC connector with ignition on. The other is the earth trigger which the ECU provides as required. Agree with both Andy's and your comments above. Once you have cleaned and lubed the AAC/IACV valve assembly the most reliable test is a direct 12V hit. If you suspect the wiring loom check the connector pins at the AAC as the first suspect. ALSO, don't forget to clean the AAC solenoid connector male pins and the wiring loom female pins ensuring the female connectors are tensioned enough to grip onto the male pins...
