495car

My original N205 resistance was out of tolerance and I just replaced it. CEL did not come on after letting engine run for about 20 minutes after the exchange. I drove it for about 4 miles and CEL came on again. Same P0011. Continuing the hunt. Any good ideas?

The car starts and runs. Maybe a little hesitation on acceleration, but not bad.

495car

I'm troubleshooting and am at the point where I'm supposed to check voltage at "socket 1/30" of the Motronic Engine Control Module Power Supply Relay (J271). I cannot find a diagram that labels the sockets! I get 12.5 v at two sockets when the key is off. I'm assuming one of those two is 1/30, and opposite 1/30 is 2/87 so that leaves either 3/86 or 4/85 as the other powered socket. The guide states I should get B+ voltage at 3/86 with the key on, but I get power at the second socket with the key in both the off and on positions. Not sure which socket is actually 3/86. I guess I can just dig down to the ECU and find the wire and do a continuity check, but I was hoping to skip that.

495car

Anyone ever remove an ECU? I've got it uncovered and out of it's plastic mount. The clamp holding the connector on is being held by headless bolts. Not funny.

495car

Finally identified the terminals and sockets. My ECM relay is the suspected culprit. I'll follow up after I've replaced it.

495car

Huge frowny face. Installed the new ECM relay this evening. After a short drive, the CEL came on. Same P0011. Ugh. Fuses are good. Wiring looks good. I'm going to start the entire troubleshooting checklist again to make sure I'm not missing anything. I'm fighting the urge to suspect the worst--the ECM. I'll keep you posted.

495car

Great news! The CEL is extinguished. I drove it a couple of days waiting for a long uninterrupted afternoon and, to my surprise, the light just went out. It's been off for a couple days now. I think it just needed a handful of drive cycles to clear it. With that being said, I am confident that the relay was the only problem. I checked the relay by applying power and checking the continuity. Simple continuity checks of the relay were not sufficient. When I applied power to the relay, the continuity value was not present. It's been a few days so I don't remember the erroneous condition, but it was wrong. I'm taking it on a couple long drives in a week so that will be the duration test. If the CEL comes on again with the same DTC, I'll provide some follow up here.

495car

CEL came on again. Then it went out again. Code reader said "P0011 intermittent." Sounds like the ECU is being temperamental. I will just keep lifting my feet as I go over bridges.