Please help! 2001 mercedes c240 has errors: ETR ignition squib R12/6 ignition circuit shorted to ground; also R12/7; and Restraint Systems ECU n2/7 ECU terminal 15r/15 under voltage

The five beeps - five times would indicate a code 55 , but factory service info only goes to code 53 .

• Audible tone - DTCs retrieved

• Air bag SRS system fault

• REFER to DTC Priority Table.

Did your air bag light flash at all ? Apparently this will do flash the air bag light codes as well .
Symptom Chart Condition Possible Sources Action

• Air bag warning indicator is illuminated continuously

• Fuse
• Damaged wiring, terminals or connectors
• A faulty diagnostic connector
• A faulted RCM
• A faulty instrument cluster

• Go To Pinpoint Test A .

• Air bag indicator flashing

• Air bag/pretensioner supplemental restraint system (SRS) fault

• REFER to DTC Priority Table.

• Audible tone - DTCs retrieved

• Air bag SRS system fault

• REFER to DTC Priority Table.

• No communication with the restraints control module (RCM)

• Fuse
• Diagnostic tool
• Data link connector (DLC)
• A faulted RCM
• Circuitry

• Go To Pinpoint Test V .

LFC - light flash codes .
Restraints Control Module (RCM) Diagnostic Trouble Code (DTC) Table
DTC a LFC b Description Action To Take - Continuous The Air Bag Indicator is Illuminated Continuously, RCM Disconnected or Inoperative, Loss of Battery Feed, or Loss of Signal Ground Go To Pinpoint Test A . B1231 13 Crash Data Memory Full Install a new RCM and impact sensors. REFER to Inspection and Repair After a Supplemental Restraint System (SRS) Deployment . B1317 Continuous Battery Voltage High CHECK battery voltage; to be below 16 volts. REFER to Section 414-01 . B1318 Continuous Battery Voltage Low CHECK battery voltage; to be above 9.0 volts. REFER to Section 414-01 . B1342 12 RCM Is Faulted Install a new RCM. B1869 NONE
Continuous lamp
Secondary air bag warning sounds if another fault is present Lamp Air Bag Warning Indicator Circuit Open or Short to Ground Go To Pinpoint Test B . B1870 NONE
Secondary air bag warning sounds if another fault is present Air Bag Warning Indicator Circuit Short to Battery Go To Pinpoint Test C . B1891 53 Air Bag Tone Warning Indicator Circuit Short to Battery Go To Pinpoint Test D . B1892 53 Air Bag Tone Warning Indicator Circuit Open or Short to Ground Go To Pinpoint Test E . B1921 14 Air Bag Diagnostic Monitor Ground Circuit Open Go To Pinpoint Test F . B2292 33 Restraint System - Safety Belt Pretensioner Fault (Driver Pretensioner Circuit Fault) Go To Pinpoint Test G . B2292 34 Restraint System - Safety Belt Pretensioner Fault (Passenger Pretensioner Circuit Fault) Go To Pinpoint Test G . B2293 19 Restraint System - Air Bag Fault (Driver Front Air Bag Circuit Fault) Go To Pinpoint Test H . B2293 21 Restraint System - Air Bag Fault (Passenger Front Air Bag Circuit Fault) Go To Pinpoint Test H . B2294 24 Restraint System - Curtain Fault (Driver Side Air Curtain Circuit Fault) Go To Pinpoint Test I . B2294 25 Restraint System - Curtain Fault (Passenger Side Air Curtain Circuit Fault) Go To Pinpoint Test I . B2295 22 Restraint System - Side Air Bag Fault (Driver Seat Side Air Bag Circuit Fault) Go To Pinpoint Test J . B2295 23 Restraint System - Side Air Bag Fault (Passenger Seat Side Air Bag Circuit Fault) Go To Pinpoint Test J . B2296 42 Restraint System - Impact Sensor Fault (Front Impact Severity Sensor Circuit Fault) Go To Pinpoint Test K . B2296 43 Restraint System - Impact Sensor Fault (Driver Side Front Row Impact Sensor Circuit Fault) Go To Pinpoint Test K . B2296 45 Restraint System - Impact Sensor Fault (Driver Side Second Row Impact Sensor Circuit Fault) Go To Pinpoint Test K . B2296 44 Restraint System - Impact Sensor Fault (Passenger Side Front Row Impact Sensor Circuit Fault) Go To Pinpoint Test K . B2296 46 Restraint System - Impact Sensor Fault (Passenger Side Second Row Impact Sensor Circuit Fault) Go To Pinpoint Test K . B2434 51 Driver Safety Belt Buckle Switch Circuit Short To Ground Go To Pinpoint Test L . B2435 51 Driver Safety Belt Buckle Switch Circuit Resistance Out Of Range Go To Pinpoint Test M . B2438 52 Passenger Safety Belt Buckle Switch Circuit Short To Ground Go To Pinpoint Test N . B2439 52 Passenger Safety Belt Buckle Switch Circuit Resistance Out Of Range Go To Pinpoint Test O . B2477 Continuous Module Configuration Error INSTALL a new RCM. B2691 51 Driver Safety Belt Buckle Switch Circuit Fault Go To Pinpoint Test P . B2692 52 Passenger Safety Belt Buckle Switch Circuit Fault Go To Pinpoint Test Q . C1414 15 Incorrect Module Design Level Go To Pinpoint Test R . C1947 49 Driver Seat Track Position Sensor Circuit Short to Ground Go To Pinpoint Test S . C1948 49 Driver Seat Track Position Sensor Circuit Resistance Out Of Range Go To Pinpoint Test T . C1981 49 Driver Seat Track Position Sensor Circuit Fault Go To Pinpoint Test U . - - No Communication with the Restraints Control Module Go To Pinpoint Test V . Your best bet have codes checked with a scan tool .

Heating and the cooling both don't work ? Just one seat or all seats ?
Your best bet have it checked for DTC'S - diagnostic trouble codes to start .
Climate Controlled Seat Module (CCSM) Diagnostic Trouble Code (DTC) Index DTC Description Source Action B1342 ECU Is Faulted CCSM INSTALL a new CCSM and CARRY OUT programmable module installation (PMI). REFER to Climate Controlled Seat Module . B1358 Ignition Switch or Blower Electronics Circuit Short to Ground CCSM Go To Pinpoint Test Q . B2477 Module Configuration Error CCSM This DTC indicates programmable module installation (PMI) has not been done to a newly installed module. CARRY OUT PMI. REFER to Section 418-01 . CLEAR the DTC. CARRY OUT the self-test. B2486 Climate Controlled Seat Module Voltage Out of Range CCSM DEPOWER the supplemental restraint system (SRS). REFER to Section 501-20B . DISCONNECT driver safety belt buckle pretensioner electrical connector or passenger safety belt buckle pretensioner electrical connector of the affected seat and CONNECT restraint system diagnostic tool 418-F395 to the safety belt buckle pretensioner harness connector. CONNECT the battery ground cable. CHECK circuit 294 (WH/LB) for a fault. REPAIR as needed. If okay, REFER to Section 414-01 . Once the repair is complete, DISCONNECT the restraint system diagnostic tool from the safety belt buckle pretensioner harness connector and CONNECT the safety belt buckle pretensioner connector of the affected seat. REPOWER the SRS. REFER to Section 501-20B . B2488 Thumbwheel Switch Voltage Out of Range High CCSM Go To Pinpoint Test R . B2521 Tach Circuit Failure CCSM Go To Pinpoint Test Q . B2729 Cushion Over-Temp Detected CCSM Go To Pinpoint Test S . B2730 Back Over-Temp Detected CCSM Go To Pinpoint Test S . B2731 Differential Temperature Fault CCSM Go To Pinpoint Test S . B2792 Heat Switch Short to Ground CCSM NOTE: If HEAT is pressed for greater than 20 seconds on the climate controlled seat switch, DTC B2792 will set in the CCSM.
CLEAR the DTC. If the DTC does not clear, DEPOWER the supplemental restraint system (SRS). REFER to Section 501-20B . DISCONNECT driver safety belt buckle pretensioner electrical connector or passenger safety belt buckle pretensioner electrical connector of the affected seat and CONNECT restraint system diagnostic tool 418-F395 to the safety belt buckle pretensioner harness connector. CONNECT the battery ground cable. CHECK circuit 1551 (VT/WH) for a short to ground. REPAIR as needed. If okay, INSTALL a new climate controlled seat switch. Once the repair is complete, DISCONNECT the restraint system diagnostic tool from the safety belt buckle pretensioner harness connector and CONNECT the safety belt buckle pretensioner connector of the affected seat. REPOWER the SRS. REFER to Section 501-20B . B2793 Cool Switch Short to Ground CCSM NOTE: If COOL is pressed for greater than 20 seconds on the climate controlled seat switch, DTC B2793 will set in the CCSM.
CLEAR the DTC. If the DTC does not clear, DEPOWER the supplemental restraint system (SRS). REFER to Section 501-20B . DISCONNECT driver safety belt buckle pretensioner electrical connector or passenger safety belt buckle pretensioner electrical connector of the affected seat and CONNECT restraint system diagnostic tool 418-F395 to the safety belt buckle pretensioner harness connector. CONNECT the battery ground cable. CHECK circuit 1550 (WH/OG) for a short to ground. REPAIR as needed. If okay, INSTALL a new climate controlled seat switch. Once the repair is complete, DISCONNECT the restraint system diagnostic tool from the safety belt buckle pretensioner harness connector and CONNECT the safety belt buckle pretensioner connector of the affected seat. REPOWER the SRS. REFER to Section 501-20B . U2362 UBP Invalid Data Node ID CCSM NOTE: DTC U2362 indicates a network concern, the CCSM is not the source of the fault.
CLEAR the DTC. If the DTC does not clear, REFER Section 418-01 .

• B1025 Component B48 (Front Passenger Seat Occupied and Child Seat Recognition) is faulty

. Were did you check for codes ? an what are you checking with ? you need a factory scan tool to check for those type codes ? or the light flashes codes
Lamp Fault Code (LFC)
When the RCM detects a fault, it will cause the air bag indicator to flash a coded sequence called a LFC. The code is one digit. The digit is indicated by a number of flashes with a 0.5 second interval between pulses. There is a 5 second pause between each display of an LFC.
Each LFC is flashed five times after which the air bag indicator will remain lit as long as the key remains in the RUN position. If there are multiple LFCs, each LFC will flash in order of priority.
Each LFC has one or more associated DTC.

1. Press TRIGGER. The RCM will run the On-Demand Self-Test and display On-Demand DTCs (reflecting hard system concerns) on the screen.

Restraints Control Module (RCM) DTC Index DTC LFC LFC Priority Description Action - Continuous 1 Air bag warning indicator is illuminated continuously Go To Pinpoint Test B . B1231 Continuous 3 Longitudinal acceleration threshold exceeded (Crash Occurred) Go To Pinpoint Test C . B1318 Continuous 4 Battery voltage low REFER to Section 414-00 . B1342 Continuous 2 RCM is defective DIAGNOSE and REPAIR other DTC(s) that are present. CLEAR the DTCs. REPEAT the self test. When or if DTC B1342 alone is present, INSTALL a new RCM. REFER to Restraints Control Module (RCM) in this section. CLEAR the DTCs. REPEAT the self test. B1462 N/A N/A Safety belt switch circuit failure Go To Pinpoint Test AN . B1869 Continuous or Tone 39 Lamp air bag warning indicator circuit open Go To Pinpoint Test AJ . B1870 Tone 41 Lamp air bag warning indicator circuit short to battery Go To Pinpoint Test AK . B1876 4 24 Safety belt driver pretensioner circuit failure Go To Pinpoint Test T . B1877 4 23 Safety belt driver pretensioner circuit open Go To Pinpoint Test S . B1878 4 22 Safety belt driver pretensioner circuit short to battery Go To Pinpoint Test R . B1879 4 36 Safety belt driver pretensioner circuit short to ground Go To Pinpoint Test AF . B1880 4 27 Safety belt passenger pretensioner circuit failure Go To Pinpoint Test W . B1881 4 26 Safety belt passenger pretensioner circuit open Go To Pinpoint Test V . B1882 4 25 Safety belt passenger pretensioner circuit short to battery Go To Pinpoint Test U . B1883 4 38 Safety belt passenger pretensioner circuit short to ground Go To Pinpoint Test AH . B1885 4 37 Safety belt driver pretensioner circuit resistance low on squib Go To Pinpoint Test AG . B1886 4 39 Safety belt passenger pretensioner circuit resistance low on squib Go To Pinpoint Test AI . B1915 3 10 Air bag driver circuit failure Go To Pinpoint Test F . B1916 3 8 Air bag driver circuit short to battery Go To Pinpoint Test D . B1920 3 13 Air bag passenger circuit failure Go To Pinpoint Test I . B1925 3 11 Air bag passenger circuit short to battery Go To Pinpoint Test G . B1932 1 9 Air bag driver circuit open Go To Pinpoint Test E . B1933 2 12 Air bag passenger circuit open Go To Pinpoint Test H . B1934 1 29 Air bag driver inflator circuit resistance low on squib Go To Pinpoint Test Y . B1935 2 31 Air bag passenger inflator circuit resistance low on squib Go To Pinpoint Test AA . B1936 3 28 Air bag driver circuit short to ground Go To Pinpoint Test X . B1938 3 30 Air bag passenger circuit short to ground Go To Pinpoint Test Z . B1992 5 14 Driver side, side mount air bag circuit short to VBATT Go To Pinpoint Test J . B1993 5 32 Driver side, side mount air bag circuit short to ground Go To Pinpoint Test AB . B1994 5 15 Driver side, side mount air bag circuit open Go To Pinpoint Test K . B1995 5 33 Driver side, side mount air bag low resistance on squib Go To Pinpoint Test AC . B1996 6 17 Passenger side, side mount air bag circuit short to VBATT Go To Pinpoint Test M . B1997 6 34 Passenger side, side mount air bag circuit short to ground Go To Pinpoint Test AD . B1998 6 18 Passenger side, side mount air bag circuit open Go To Pinpoint Test N . B1999 6 35 Passenger side, side mount air bag low resistance on squib Go To Pinpoint Test AE . B2117 5 16 Driver side, side mount air bag low capacitance on squib Go To Pinpoint Test L . B2118 6 19 Passenger side, side mount air bag low capacitance on squib Go To Pinpoint Test O . B2141 5Hz 6 NVM configuration failure RECONFIGURE the RCM. REFER to Section 418-01 . B2226/ B2227/ B2855/ B2856 N/A N/A Front crash sensor failure Go To Pinpoint Test AR . B2228/ B2230/ B2232/ B2234 N/A N/A Air bag driver, 2nd stage fault Go To Pinpoint Test AL . B2229/ B2231/ B2233/ B2235 N/A N/A Air bag passenger, 2nd stage fault Go To Pinpoint Test AM . B2433/ B2434/ B2435 N/A N/A Buckle switch, driver failure Go To Pinpoint Test AO . B2437/ B2438/ B2439 N/A N/A Buckle switch, passenger failure Go To Pinpoint Test AP . B2477 Continuous 7 Module configuration failure Check for correct RCM for this vehicle. RECONFIGURE the RCM. REFER to Section 418-01 . B2853/ B2854/ B2873/ B2873/ U2027 5 20 Left side crash sensor internal fault/short to ground/VBATT/ID fault Go To Pinpoint Test P . B2852/ B2874/ B2875/ U2028 6 21 Right side crash sensor internal fault/short to ground/VBATT/ID fault Go To Pinpoint Test Q . C1947/ C1948/ C1982 N/A N/A Seat track position sensor, driver failure Go To Pinpoint Test AQ .

Fuse Terminal Cable ID (fused) Fused function Rating in amperes (A) F1 30 - Wiper park position heater relay (K40/2kA) F2 30 - High pressure and return flow pump relay (K40/2kF) F3 30 - Steering column forward/back adjustment relay 1 (K40/2kD)
Steering column forward/back adjustment relay 2 (K40/2kE) F4 30 - Steering column height adjustment relay 1 (K40/2kI)
Steering column height adjustment relay 2 (K40/2kJ) F5 15R - Wiper On and Off relay (K40/2kH) F8 30 RD 0.75 Central gateway control unit (N93) F9 30 PKWH 2.5 Left door control unit (N69/1) F10 15 BKVT 0.75
BKVT 0.75
BKVT 0.75 Left front headlamp unit (E1)
Right front headlamp unit (E2)
Xenon headlamp control unit (E1n1, E2n2) 15 RDGN 0.75 Restraint systems control unit (N2/7) F11 15R BKYE 1.0 Circuit 15R/30 cutoff relay (K75) F12 15R - Spare F13 30 RDGN 1.5 ABC control unit (N51/2) F14 15R BKGN 0.75 Windshield washer fluid pump (M5/1) F15 30 RDGN 1.0 Data link connector (X11/4) F16 15R PKYE 1.0 Valid for code (855) TELE AID:
D2B telephone and TELE AID transmitter/receiver (A35/17) 15R PKYE 1.0 Valid for code (853) MB standard telephone:
D2B telephone transmitter/receiver (A35/13) F17 15R RDYE 0.5 Vehicle-sensitive seat belt lock sensor (A60) F18 15R - Spare F19 15 BKYE 1.00 Valid for engines 112.973, 113.963/992:
Fused via circuit 15 connector sleeve (Z3/29):
Cylinder 1 ignition coil (T1/1)
Cylinder 2 ignition coil (T1/2)
Cylinder 3 ignition coil (T1/3)
Cylinder 4 ignition coil (T1/4)
Cylinder 5 ignition coil (T1/5)
Cylinder 6 ignition coil (T1/6)
Cylinder 7 ignition coil (T1/7)
Cylinder 8 ignition coil (T1/8) F20 15 BKGN 0.75 Data link connector (X11/4) F21 15R BKYE 0.5 Instrument cluster (A1) F22 30 RDYE 0.5 Instrument cluster (A1) F23 30 RDWH 1.0
RDWH 1.0 AAC [KLA] control and operating unit (N22)
Coolant circulation pump (M13) F24 30 RDWH 0.5 Stop lamp switch (S9/1) F25 30 RDYE 0.75 Alarm signal horn (H3) F26 30 RDBU 0.5 Lower control panel control unit (N72) F27 30 RDVT 2.5 Left front seat adjustment control unit with memory (N32/1)

Error Code: DTC P1300
Description: Igniter Circuit Malfunction
Solution:
To repair the code please do the following:
1. Check spark plugs.
2. Check for open and short in harness and connector in IGF (Ignition Confirmation) signal circuit between ECM and igniter.
3. Disconnect igniter connector and check voltage between terminal IGF of ECM connector and body ground.
4. Check for open and short in harness and connector in IGT1 - 3 signal circuit between ECM and igniter.
5. Check voltage between terminals IGT1 - 3 of ECM connector and body ground.
6. Disconnect igniter connector and check voltage between terminals IGT1 - 3 of ECM connector and body ground.
8. Check for open and short in harness and connector between ignition switch and ignition coil, ignition coil and igniter.
9. Check and replace ignition coils with a good known one.
10. Check and replace ECM with good a known one .
Hope that works.
Thank you for visiting Fixya.

Go to Advance Auto or Auto Zone and ask them to read the error codes. Then lookup those codes on the Internet or post them on https://mbworld.org/

• B0041

CIRCUIT DESCRIPTION
The inflatable restraint side impact module-LF deployment loop consists of the inflatable restraint side impact module-LF, the inflatable restraint side impact module wiring harness, and the side impact module-LF high and low circuits. A shorting bar used within the side impact module-LF connector shorts together the side impact module-LF high and low circuits when the connector is disconnected. This helps to prevent unwanted deployment of the inflator module during servicing. During a side or frontal crash of sufficient force the inflatable restraint Sensing and Diagnostic Module (SDM) allows current to flow through the deployment loop in order to deploy the side impact module-LF. When the ignition is turned ON, the SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a Diagnostic Trouble Code (DTC) will be stored in memory.

CONDITIONS FOR RUNNING THE DTC
Ignition 1 voltage is within the normal operating voltage range.

CONDITIONS FOR SETTING THE DTC

• DTC B0040 will set when the side impact module-LF deployment loop resistance is less than 1.3 ohms for 500 milliseconds .
• DTC B0041 will set when one of the following conditions occurs:
• Side impact module-LF high circuit is less than 2.4 volts and the side impact module-LF deployment loop is more than 6 ohms for 500 milliseconds .
• Side impact module-LF deployment loop resistance is more than 4.8 ohms for 500 milliseconds .
• DTC B0045 will set when one of the following conditions occur:
• Side impact module-LF high and/or low circuits is short to ground or short to voltage for 500 milliseconds .
• Side impact module-LF high circuit is less than 2.4 volts and side impact module-LF deployment loop resistance is less than 6 ohms for 500 milliseconds .

ACTION TAKEN WHEN THE DTC SETS
The SDM commands the AIR BAG indicator ON via Class 2 serial data.

CONDITIONS FOR CLEARING THE DTC

• The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
• A history DTC will clear once 255 malfunction free ignition cycles have occurred.

DIAGNOSTIC AIDS
The following are possible causes of the malfunction:

• A short between the side impact module-LF high and low circuits
• An open or a high resistance in the side impact module-LF high or low circuits
• A short to ground or a short to voltage in the side impact module-LF high or low circuits
• The side impact module-LF connector
• The SDM connector
• A malfunctioning side impact module-LF
• A malfunctioning SDM

I have a 2001 C240 with the same issue. I removed the positive battery cable from the battery and kept it off for 30 seconds then replaced it. Everything was reset and the key worked.

Control Unit N2/7 (Restraints Systems Control Unit) is defective.
Here is where the unit is located;
http://ww2.justanswer.com/uploads/eurotec/2009-06-05_014107_Remove_install_airbag_belt_tensioner_control_unit.pdf