ECU stopped communicating with ScanGauge
#1
ECU stopped communicating with ScanGauge
My ECU has only limited communication with the ScanGauge: displays volts, RPM, horsepower and throttle position sensor. Does not show water or air temp, closed or open loop, nor oxygen sensors. This happened the previous winter, but everything came back when it dried out in spring. So far this year, no such luck.
I also cannot read or clear trouble codes. I have inspected and cleaned all the connections to the ECU, to no avail. I've also disassembled and cleaned all the ground headers, with the exception of the one in left front footwell (that one was unbolted from body and lug cleaned, but did not remove connector.)
Anyone else ever had this symptom? Any resolution ideas?
Oh-- And it's not the gauge. Works fine in the wife's' jeep.
I also cannot read or clear trouble codes. I have inspected and cleaned all the connections to the ECU, to no avail. I've also disassembled and cleaned all the ground headers, with the exception of the one in left front footwell (that one was unbolted from body and lug cleaned, but did not remove connector.)
Anyone else ever had this symptom? Any resolution ideas?
Oh-- And it's not the gauge. Works fine in the wife's' jeep.
Last edited by NickAdams; 05-21-2016 at 07:53 AM. Reason: Added info.
#2
#4
Happens often with mine, because I have a scanner plugged in all of the time (its a rover).
I suppose it is possible that there is oxidation or some other stuff on the connectors but oh what a pain to spray electronics cleaner on them in the cabin. I'd exhaust all other possibilities first. But I can't think of any other possibilities at the moment. I've never found where the obdii port ends at the ECU, but if you can spot the wire colors that connector that might be the next one to check.
NOT doubting that the UG is good, but have you tried another scanner on the obdii port? If it is oxidation you could just plug and unplug again and again to knock of anything on the connectors.
#6
Pull my ECU, maybe. Charlie's suggestion did cause me to pull apart the on-board OBD II connector. Which helped me see the (4) wires connected to it: one purple, one mauve, two black. (The Rave electrical diagram is at home; I'm at work.) Seeing what part of the harness the wires are in, I was convinced the two black (ground?) wires terminated at the header in the right footwell. So I pulled that out and lo and behold there was a small amount of corrosion in the connector. Clean and shiny now, but no change in scan performance.
I hadn't thought of hooking up a different scan tool, but like I said, this scangauge 2 works fine in her jeep.
I hadn't thought of hooking up a different scan tool, but like I said, this scangauge 2 works fine in her jeep.
#7
Sorry for the hijack!
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