99 S70 non turbo ETS light problem

traveader · Post by **traveader** » 23 May 2010, 00:34

The car has 127K miles on it. The ETM is still the original unit (white sticker). I had experiences of acceleration hesitation in the 50-60 mph range while driving in mountain areas, which was kind of scary. Other than that, the car has been running fine to this day and does not seem to have the erratic idle issue. The ETS light came on for the first time two weeks ago and went off by itself a couple of hours later when I restarted the car. Three days later it came back on and stayed on. I sent the car to a local independent shop (not specialized in Volvo). The mechanic said the ABS hydrolic module fuse was off and according to him once it was replaced the ETS went off. He did not charge me anything but suggested I go back in two weeks to get the rear brakes job done. A week later the ETS came back on again and stayed on. I called that mechanic again, asking about the codes, and was told there had been no codes. Unsatisfied with the answer, I drove the car to another independent shop 40 miles away from where I live, this time a Volvo specialist. The mechanic checked the car and said the software had been upgraded before. The codes I got were: ECM-9150 throttle position sensor 1 faulty signal - DTC is found not active. However, for the ETM itself it says "no fault found". Three other codes are: CCM-414 fan motor passenger compartment temperature sensor faulty signal, CDM-0001 vehicle speed signal missing, IMM-321 initiation signal from the engine control modue (ECM) missing. I decided to try cleaning up the ETM for now (I am planning to use XeMODex by the way). After the mechanic cleaned it, the ETS light went off and the mechanic showed me the test with the potentiometer difference chart, from which the module seemed to be running fine (the difference values were within the limit). I am going to replace the aging ETM anyway for the peace of mind, but the questions that I have are: does the diagnosis of"ETM no fault found" mean the ETM is OK? How many miles might be left on the ETM? Do other codes have anything to do with the ETS light problem at all? Any insight will be appreciated.

traveader · Post by **traveader** » 31 May 2010, 20:03

Well, the ETS light went off by itself today after staying on for nearly a week. I've been waiting for the new ETM from XeMODex to arrive (UPS delivery was supposed to be 3 days by air, but it was delayed and then further delayed due to the Memorial Day weekend, so it's actually going to take 6 days), but I start to wonder whether it is something else that is wrong.

traveader · Post by **traveader** » 02 Jun 2010, 23:10

I just got the original ETM replaced with the XeMODex one. The ETS light went off, but it is yet to see whether it will come back on again. In the meanwhile, with the new ETM, I notice that when the engine just gets started, the car in the park mode, the tachometer shoots up to 1200rpm something then fluctuates around 1000 rpm then slowly goes down to 900. When coasting in the 30-40 mph speed range, I notice the tachometer would drop suddenly, say, from 2000 rpm to 1600 rpm. Is it functioning all right?

Post by **mikealder** » 14 Aug 2010, 07:44

I would be rather concerned about this fault code:

ECM-9150 throttle position sensor 1 faulty signal

If the throttle position sender is on its way out then it will cause the ETS light and rough engine control, if the ETM was reading in spec on the resistance checks then I doubt it was faulty although tests such as these are not fully representative due to a lack of heat and vibration such as you get when driving - Mike

traveader · Post by **traveader** » 15 Aug 2010, 16:12

dmdaws wrote:I'm all ears. Are you satisfied with the new ETM? Has the light stayed off?
thanks...I'm at 150k and trying justify putting another $600 in my v70 given my only problem is a) the light and b) rough starts in the morning

The ETS light seems to be gone for good. The unit has been working perfectly.