can't turn off tow alarm, other issues
07-18-2019, 09:55 PM
#1
Member
Thread Starter
can't turn off tow alarm, other issues
Newbie here, so go easy. I've tried searching.
Car I just bought with some electrical issues. I've tried searching for a number of issues, and it's either the wrong car, or I can't find the answer. I'm hoping for some help or to be pointed in the right direction
1) If you hit the off button on the tow alarm, should the indicator light keep flashing? I can't get it to turn off, pushing or holding the button. Key is not in the ignition
2) If I turn on the headlights, the drivers door lock machine-guns, and the passenger locks.
3) Then the rear flashers go off, even though the hazard light button is not depressed. Turning the head lights off and on seems to clear this; it doesn't go off by itself
4) The rear hatch green button does not work, and the fob does not unlock it.
5) The car does run, but not responding to throttle
6) FWIW, the interior lights come on when the door is opened, and go off after a few minutes, as they should. The brake lights work.
I'm going to go through all the fuses this weekend, but it's always nice if someone has been down this road. Thanks.
I'd like to order a service manual, and I have a message into a mercedes oem site. However, the sticky is all posts going on ten years old. Are manuals still available? If not, what's the best resource? Sticky doesn't answer that.
I've done some reading on rear SAM's going bad after a battery change, but haven't read about this particular combination of symptoms.
Any help appreciated, or point me in the right direction. thanks.
Car I just bought with some electrical issues. I've tried searching for a number of issues, and it's either the wrong car, or I can't find the answer. I'm hoping for some help or to be pointed in the right direction
1) If you hit the off button on the tow alarm, should the indicator light keep flashing? I can't get it to turn off, pushing or holding the button. Key is not in the ignition
2) If I turn on the headlights, the drivers door lock machine-guns, and the passenger locks.
3) Then the rear flashers go off, even though the hazard light button is not depressed. Turning the head lights off and on seems to clear this; it doesn't go off by itself
4) The rear hatch green button does not work, and the fob does not unlock it.
5) The car does run, but not responding to throttle
6) FWIW, the interior lights come on when the door is opened, and go off after a few minutes, as they should. The brake lights work.
I'm going to go through all the fuses this weekend, but it's always nice if someone has been down this road. Thanks.
I'd like to order a service manual, and I have a message into a mercedes oem site. However, the sticky is all posts going on ten years old. Are manuals still available? If not, what's the best resource? Sticky doesn't answer that.
I've done some reading on rear SAM's going bad after a battery change, but haven't read about this particular combination of symptoms.
Any help appreciated, or point me in the right direction. thanks.
08-15-2019, 12:35 PM
#3
Member
Thread Starter
Just a reminder of what's wrong. The car runs, but has a lousy loping idle. About nothing else works, though I need to get a detailed list of that together. Locks, with me just sitting in the car, rapid fire every couple of minutes. Cluster gets SRS, and brake fluid level errors, plus I've gotten ECS and cluster errors too. Rear light comes on when the hatch is manually opened from inside (inside button doesn't work)
The throttle usually loses it's calibration and has to be reset every time I start the car. Usually, but not always.
I have done a lot of searches, and problems were either something else, or the thread died before the OP said what the problem was. Very frustrating.
**If someone with some experience wants to read through this, and tell me if my next steps (laid out at the bottom) make sense. Am I missing something obvious?
BTW, I bought the car cheap, when a previous owner gave up. While I may eventually take it to an Indy shop, I bought the car as a learning exercise (and because I'm a masochist), so I'm at this point I'm determined to stay with it until I find something.
Here's what I've done so far:
Read codes: P0600 communication link to CAN, and P0010 Camshaft position actuator circuit open bank 1: P0120 throttle/pedal psoition sensor A circuit
replaced intake cam sensor and magnet
replaced ECU (previous owner did this, didn't change anything. I still have the original)
pulled and checked all fuses
checked the prefuses
checked the battery voltage (12.75v just sitting, and doesn't change over a couple of days)
pulled and checked all relays for operation and connection
pulled fuses for radio, door locks, and sunroof- just to eliminate them from consideration
unplugged alarm siren in fender well for the same reason
replaced key fob battery (still shows not working with IR, according to Autozone checker)
Checked voltages on all CAN x-connectors. Got 11.43v on one and .43v on the other, no matter what I disconnected (excepting the interconnects)- [The latter number is supposed to be like .025v I think]
I bought an MBII, and it said:
P2041-000, P2054-000, P202C-000,
B100C Output Circuit 15 short circuit to positive
B1002 overvoltage supply
B1001 undervoltage supply
C1035 N49 steering angle sensor
C1024
C1212 overvoltage at terminal 30
C1210 undervoltage at terminal 30
B34/1 ESP pressure sensor and B34 ESP brake pressure sensor- plausibility error
B24/15 yaw rate sensor AY pickup overvoltage or B24/15 rotary speed and lateral acc sensor overvoltage
Since it couldn't talk to the CAN, a lot of the module results were "fault in communication with the ECU"
My next steps will be to put the fuses I removed back in, and get a better list of what's not working.
Then, since I'm sure it needs to be done either way, I'll pull the throttle body and MAF for cleaning and checking, redo the crankcase vent lines, and change the supercharger oil.
The throttle usually loses it's calibration and has to be reset every time I start the car. Usually, but not always.
I have done a lot of searches, and problems were either something else, or the thread died before the OP said what the problem was. Very frustrating.
**If someone with some experience wants to read through this, and tell me if my next steps (laid out at the bottom) make sense. Am I missing something obvious?
BTW, I bought the car cheap, when a previous owner gave up. While I may eventually take it to an Indy shop, I bought the car as a learning exercise (and because I'm a masochist), so I'm at this point I'm determined to stay with it until I find something.
Here's what I've done so far:
Read codes: P0600 communication link to CAN, and P0010 Camshaft position actuator circuit open bank 1: P0120 throttle/pedal psoition sensor A circuit
replaced intake cam sensor and magnet
replaced ECU (previous owner did this, didn't change anything. I still have the original)
pulled and checked all fuses
checked the prefuses
checked the battery voltage (12.75v just sitting, and doesn't change over a couple of days)
pulled and checked all relays for operation and connection
pulled fuses for radio, door locks, and sunroof- just to eliminate them from consideration
unplugged alarm siren in fender well for the same reason
replaced key fob battery (still shows not working with IR, according to Autozone checker)
Checked voltages on all CAN x-connectors. Got 11.43v on one and .43v on the other, no matter what I disconnected (excepting the interconnects)- [The latter number is supposed to be like .025v I think]
I bought an MBII, and it said:
P2041-000, P2054-000, P202C-000,
B100C Output Circuit 15 short circuit to positive
B1002 overvoltage supply
B1001 undervoltage supply
C1035 N49 steering angle sensor
C1024
C1212 overvoltage at terminal 30
C1210 undervoltage at terminal 30
B34/1 ESP pressure sensor and B34 ESP brake pressure sensor- plausibility error
B24/15 yaw rate sensor AY pickup overvoltage or B24/15 rotary speed and lateral acc sensor overvoltage
Since it couldn't talk to the CAN, a lot of the module results were "fault in communication with the ECU"
My next steps will be to put the fuses I removed back in, and get a better list of what's not working.
Then, since I'm sure it needs to be done either way, I'll pull the throttle body and MAF for cleaning and checking, redo the crankcase vent lines, and change the supercharger oil.
Last edited by nlinesk8s; 08-15-2019 at 12:38 PM.
11-29-2019, 09:24 AM
#4
Member
Thread Starter
Unlike most all the threads I found on similar situations, I'm going to tell you the final resolution. This car had multiple checks, no fuses or relays were bad, I disconnected everything that might have been a problem, AND replaced the rear SAM. I still couldn't talk to the electronics of the car. The previous owner replaced the ECU.
It turned out to be the front SAM. Had I continued replacing parts in hopes of fixing the issue, that was going to be my next step. But I gave it to an Indy shop who spent a considerable amount of time finding the issue. Oh well. I think my advice here to anyone facing similar problems would be to leverage Ebay for both SAM's, make sure your battery is in good condition, and check everything you can with a multimeter and scan tool.
It turned out to be the front SAM. Had I continued replacing parts in hopes of fixing the issue, that was going to be my next step. But I gave it to an Indy shop who spent a considerable amount of time finding the issue. Oh well. I think my advice here to anyone facing similar problems would be to leverage Ebay for both SAM's, make sure your battery is in good condition, and check everything you can with a multimeter and scan tool.
