My cars check engine light came on today so i went through and checked the codes and all of them had H by them for history except for the RTD. What does it mean when the RTD has lost communictions and how do i fix it?

 

should i clear all the other codes and see which ones come back?

 

Initially, on-board diagnostics go into an "Automatic Mode" which shows diagnostic codes in a pre-set sequence: PCM - TCS - RTD (Real Time Damping) - BCM - IPC - RADIO - HVAC - LDCM - RDCM - SCM - RFA. All codes will be displayed for each module. If none are present in a given module, you will see "No More Codes" on the display.

38-RTD - Real Time Damping
C1650 ESC Module Malfunction
C1658 EEPROM Calibration Malfunction
C1710 LF Shock Absorber Solenoid (Short to Voltage)
C1711 LF Shock Absorber Solenoid (Short to GND)
C1712 LF Shock Absorber Solenoid (Open Circuit)
C1715 RF Shock Absorber Solenoid (Short to Voltage)
C1716 RF Shock Absorber Solenoid (Short to GND)
C1717 RF Shock Absorber Solenoid (Open Circuit)
C1720 LR Shock Absorber Solenoid (Short to Voltage)
C1721 LR Shock Absorber Solenoid (Short to GND)
C1722 LR Shock Absorber Solenoid (Open Circuit)
C1725 RR Shock Absorber Solenoid (Short to Voltage)
C1726 RR Shock Absorber Solenoid (Short to GND)
C1727 RR Shock Absorber Solenoid (Open Circuit)
C1743 Loss of Vehicle Speed Signal
C1760 LF Position Sensor (Out of Range)
C1761 RF Position Sensor (Out of Range)
C1762 LR Position Sensor (Out of Range)
C1763 RR Position Sensor (Out of Range)
C1768 Position Sensor Supply Malfunction (Overcurrent)
C1780 Loss of Steering Position Signal
C1786 RTD Control Relay Malfunction
C1787 RTD Control Relay Circuit (Open or Short to GND)
C1788 RTD Control Relay Circuit (Short to Voltage)
C1790 Ride Control Switch (Out of Range)
C1791 Ride Control Switch (Contact Malfunction)


I would write them down, reset them and monitor for a while to see if any come back. Next time, please post the specific error code so we can be more helpful. Good luck.
John

 

If you dont post the code all you will get is a SWAG on what you should do. Please post the codes. Make sure that you include if they are H, HC or C.

Bill

 

it doesnt give me any codes. when it comes to the RTD it waits a second like its looking for it and then comes back saying NO COMM.

 

Ok. I went through the diagnostics again and heres the codes it gave me.
P1571 H- Traction control torque request circuit
C1226 H-RF Excessive wheel speed variation
B2723 H- PASS- Key Detection Circuit
U1064 H- Lost Communication with BCM
RTD- No COMM.

 

I'm not 100% sure but your car may not be equipped with RTD, this will definitely give you a "no comm" message.

Either way a problem with your RTD will not cause a check engine light to illuminate, the P1571 is causing that, I say rest all your codes and try it again.

 

Thanks. I will do that and see if it comes back.

 

Is your car equiped with the F-45 (Selective Ride) option? If it is not, you will have a NO COMMS as a normal condition. If you do have it, check the following:
Maxi Fuse# 53
Ground connection G-402 and G401

You can tell if you have selective ride if you have a switch on your center console that allows you to select suspension settings like Tour, Sport and Performance.

Your Electronic Brake Traction Module (EBTCM) is a rear mounted version. It is subject to severe weather conditions and road salts. There is a good chance that the ground connection on the module is corroded. Examine the ground, soak it in penerating oil and very carefuly disconnect and clean it.

How old and what condition is your battery in?

Bill

 

The car does not have selective ride control so that solves that question. the battery is not more than a year old but it keeps dying on me.

 

How often does it discharge? Do you park it for an extended period of time?

 

i never leave it sit for more than two days at the most. the time i find it dies the most is if i leave the radio on for like 10 mins with the car not running, when i go to start it it just doesnt seem like the battery has a full charge. What is the normal battery voltage when the car is running?

 

You need a new battery!!! You should be able to play your radio for quite a while without an issue. The battery is most likley contributing to all of your codes! I bet if you put a new battery, you will fine that you get rid of a lot of problems!

You should be charging at around 13.5 - 14.5 Volts.

Bill C

 

thanks for the help. that was what i thought the car never charged above 13.5 when it was running.

 

What is your actual voltage at the battery terminals?? The meter can be low by a good deal!!! Read the charging voltage at the battery.

Bill