HS-CAN and MS-CAN
WARNING: This page is about a different car, the 2007 Lincoln MKX and 2007 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.
CAN is a communication network that uses an unshielded twisted pair cable of data (+) and data (-) circuits. The data (+) and the data (-) circuits are each regulated to approximately 2.5 volts during neutral or rested network traffic. As bus messages are sent on the data (+) circuit, voltage is increased by approximately 1.0 volt. Inversely, the data (-) circuit is reduced by approximately 1.0 volt when a bus message is sent. Multiple bus messages can be sent over the network CAN circuits allowing multiple modules to communicate with each other.
The MS-CAN network operates at a maximum data transfer speed of 125 Kbps for bus messages and is designed for general information transfer. The HS-CAN network operates at a maximum data transfer speed of 500 Kbps and is designed for real time information transfer and control.
Certain network faults may cause inconsistent message communication. The CAN network may remain operational with only 1 of the 2 termination resistors present.
The following fault chart describes the specific CAN network failures and their resulting symptom:
CAN NETWORK COMMUNICATION FAULT CHART
| Failure Description | Symptom |
|---|---|
| CAN (+) shorted to CAN (-) | No communication |
| CAN (+) short to voltage | No communication |
| CAN (-) short to voltage | No communication |
| CAN (+) short to ground | No communication |
| CAN (-) short to ground | Unreliable communication |
| CAN (+) open | Unreliable communication |
| CAN (-) open | Unreliable communication |
| Module loss of voltage or ground | No communication |
| Module internal failure | No communication |
NOTE:
Some HS-CAN faults may result in a no-start condition.
CAN NETWORK MODULE COMMUNICATION MESSAGE CHART
| Broadcast Message | Originating Module | Network Type | Receiving Module(s) |
|---|---|---|---|
| ABS event in progress | ABS module | HS-CAN |
|
| ABS malfunction indicator request | ABS module | HS-CAN |
|
| A/C clutch request | Electronic automatic temperature control (EATC) module | MS-CAN |
|
| A/C clutch request (gateway) | Instrument cluster | HS-CAN |
|
| A/C clutch status | PCM | HS-CAN |
|
| A/C clutch status (gateway) | Instrument cluster | MS-CAN |
|
| A/C pressure | PCM | HS-CAN |
|
| A/C pressure (gateway) | Instrument cluster | MS-CAN |
|
| Accelerator pedal position | PCM | HS-CAN |
|
| Accessory delay status | Smart junction box (SJB) | MS-CAN |
|
| Adaptive headlamp failure status | Adaptive front lighting module | HS-CAN |
|
| Airbag deployment event status | RCM | HS-CAN |
|
| Airbag malfunction indicator request | RCM | HS-CAN |
|
| Ambient temperature | EATC module | MS-CAN |
|
| Autolamp delay request | Instrument cluster | MS-CAN |
|
| Autolamp delay status | SJB | MS-CAN |
|
| Auto Lock command | Instrument cluster | MS-CAN |
|
| Auto Lock status | SJB | MS-CAN |
|
| Auto unlock command | Instrument cluster | MS-CAN |
|
| Auto unlock status | SJB | MS-CAN |
|
| AWD coupling mode and status | 4WD control module | HS-CAN |
|
| AWD malfunction indicator request | 4WD control module | HS-CAN |
|
| Axle ratio | PCM | HS-CAN |
|
| Barometric pressure | PCM | HS-CAN |
|
| Barometric pressure (gateway) | Instrument cluster | MS-CAN |
|
| Brake fluid level status | SJB | MS-CAN |
|
| Brake fluid level status (gateway) | Instrument cluster | HS-CAN |
|
| Brake malfunction indicator request | ABS module | HS-CAN |
|
| Charging system malfunction indicator request | PCM | HS-CAN |
|
| Climate controlled seat setting | EATC module | MS-CAN |
|
| Climate controlled seat status | Climate controlled seat module | MS-CAN |
|
| Daytime running lamp (DRL) status | SJB | MS-CAN |
|
| Door ajar status | SJB | MS-CAN |
|
| Door ajar status (gateway) | Instrument cluster | HS-CAN |
|
| Door lock switch inhibit status | SJB | MS-CAN |
|
| Easy entry/exit command | Instrument cluster | MS-CAN |
|
| Easy entry/exit status | DSM | MS-CAN |
|
| Engine coolant temperature | PCM | HS-CAN |
|
| Engine coolant temperature (gateway) | Instrument cluster | MS-CAN |
|
| Engine fuel consumption data | PCM | HS-CAN |
|
| Engine malfunction indicator lamp (MIL) request | PCM | HS-CAN |
|
| Engine off timer | PCM | HS-CAN |
|
| Engine off timer (gateway) | Instrument cluster | MS-CAN |
|
| Engine RPM | PCM | HS-CAN |
|
| Engine RPM (gateway) | Instrument cluster | MS-CAN |
|
| Engine torque data | PCM | HS-CAN |
|
| Engine torque reduction request | ABS module | HS-CAN |
|
| English/metric language | Instrument cluster | MS-CAN |
|
| Engine fail-safe cooling mode status | PCM | HS-CAN |
|
| Engine fail-safe electronic throttle control (ETC) status | PCM | HS-CAN |
|
| Fuel cap off indicator request | PCM | HS-CAN |
|
| Fuel level input status (instant), sender 1 & 2 | Instrument cluster | HS-CAN |
|
| Headlamp high beam indicator request | SJB | MS-CAN |
|
| Headlamp status | SJB | MS-CAN |
|
| Headlamp warning chime request | SJB | MS-CAN |
|
| Ignition switch position | Instrument cluster | HS-CAN |
|
| Ignition switch position | SJB | MS-CAN |
|
| Illumination dimmer level | SJB | MS-CAN |
|
| Integrated key head transmitter (IKT) program request | Instrument cluster | MS-CAN |
|
| IKT data | Instrument cluster | MS-CAN |
|
| IKT program response | SJB | MS-CAN |
|
| IKT button status | SJB | MS-CAN |
|
| Key-in-ignition status | SJB | MS-CAN |
|
| Key-in-ignition chime request | SJB | MS-CAN |
|
| Navigation radio rolling wheel count | ABS module | HS-CAN |
|
| Navigation radio rolling wheel count (gateway) | Instrument cluster | MS-CAN |
|
| OCS data | Occupant classification sensor module | HS-CAN |
|
| OCS serial number and calibration | Occupant classification sensor module | HS-CAN |
|
| Odometer count | PCM | HS-CAN |
|
| Parking aid disable switch status | Instrument cluster | MS-CAN |
|
| Parking aid sounder audio mute command | Parking aid module | MS-CAN |
|
| Parking aid system status | Parking aid module | MS-CAN |
|
| Parking brake status | SJB | MS-CAN |
|
| Parking brake status (gateway) | Instrument cluster | HS-CAN |
|
| PATS OK to start | Instrument cluster | HS-CAN |
|
| PATS security data | Instrument cluster | HS-CAN |
|
| PATS security data | PCM | HS-CAN |
|
| PATS theft condition | PCM | HS-CAN |
|
| Power liftgate enable/disable | Instrument cluster | MS-CAN |
|
| Power liftgate command | SJB | MS-CAN |
|
| Power liftgate status | Power liftgate module | MS-CAN |
|
| RCM serial number and calibration | RCM | HS-CAN |
|
| Safety belt indicator request | RCM | HS-CAN |
|
| Safety belt indicator status | Instrument cluster | HS-CAN |
|
| Safety belt minder chime/flash request | RCM | HS-CAN |
|
| Speed control indicator request | PCM | HS-CAN |
|
| Stability control chime request | ABS module | HS-CAN |
|
| Stability control event in progress | ABS module | HS-CAN |
|
| Steering wheel angle | Steering angle sensor module | HS-CAN |
|
| Steering wheel calibration status | Steering angle sensor module | HS-CAN |
|
| Tire pressure monitoring system (TPMS) status | SJB | MS-CAN |
|
| TPMS sensor status (LF, RF, RR, LR, spare) | SJB | MS-CAN |
|
| Tire size information | ABS module | HS-CAN |
|
| Torque transfer data | 4WD control module | HS-CAN |
|
| Traction control enabled status | Instrument cluster | HS-CAN |
|
| Traction control event in progress | ABS module | HS-CAN |
|
| Trailer brake lamp enabled status | Instrument cluster | MS-CAN |
|
| Transmission gear ratio | PCM | HS-CAN |
|
| Transmission malfunction indicator request | PCM | HS-CAN |
|
| Transmission overdrive cancel indicator status | PCM | HS-CAN |
|
| Transmission selector (PRNDL) range | PCM | HS-CAN |
|
| Transmission selector (PRNDL) range (gateway) | Instrument cluster | MS-CAN |
|
| Transmission shift in progress | PCM | HS-CAN |
|
| Turn signal request | SJB | MS-CAN |
|
| Vehicle speed | PCM | HS-CAN |
|
| Vehicle speed (gateway) | Instrument cluster | MS-CAN |
|
| VIN information | PCM | HS-CAN |
|
| VIN information (gateway) | Instrument cluster | MS-CAN |
|
| Wheel speed output (RF, LF, RR, LR) | ABS module | HS-CAN |
|