Mariner 2WD V6-3.0L VIN 1 (2006)
Information Bus: Description and Operation
COMMUNICATIONS NETWORK
Smart Junction Box (SJB)
The SJB is connected to the medium speed controller area network (CAN) communications bus. If one of the bus wires becomes shorted to ground or
voltage, communications can continue at a reduced level. Check circuits 1847 (WH/OG), and 1848 (PK/OG) between the SJB C2280a, the instrument
cluster C220 and the data link connector (DLC) C251. Total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms,
there is an open circuit in the medium speed CAN, damage to the DLC C251, or damage to the SJB C2280a. Since both the SJB and the instrument
cluster share network termination responsibilities, a problem in either of these modules can result in a medium speed CAN failure.
Powertrain Control Module (PCM)
The PCM is on the high speed CAN. The PCM controls the engine for better fuel economy, emissions control, failure mode detection and storage, and
all passive anti-theft system (PATS) functions. If one of the bus wires becomes shorted to ground or voltage, communications can continue at a
reduced level. Check the high speed CAN circuits 1908 (WH) and 1909 (BK), between the PCM C175b and the DLC C251. Total resistance values
must not be more than 5 ohms. If the resistance is more than 5 ohms, there is an open circuit in the high speed CAN, damage to the DLC C251,
damage to the PCM C175b, or a problem in the in-line connector. Since both the PCM and the instrument cluster share network termination
responsibilities, a problem in either of these modules can result in a high speed CAN failure.
Instrument Cluster
The instrument cluster is on the high speed CAN. It is an analog face cluster with a digital odometer. The instrument cluster displays a variety of
information. If one of the bus wires becomes shorted to ground or voltage, communications can continue at a reduced level. Check the high speed
CAN circuits 1908 (WH) and 1909 (BK) between the instrument cluster C220 and the DLC C251. Total resistance values must not be more than 5
ohms. If the resistance is more than 5 ohms, there is an open circuit in the CAN, damage to the DLC C251, damage to the instrument cluster C220, or
a problem in the in-line connector. Since both the PCM and the instrument cluster share network termination responsibilities, a problem in either of
these modules can result in a high speed CAN failure.
Restraint Control Module (RCM)
The RCM is on the international standards organization (ISO) 9141 communication network. The RCM controls the deployment of the air bags based
on sensor input. The ISO 9141 communication network does not function if the wire is shorted to ground or battery voltage. Check the network circuit
between the RCM C2041a and the DLC C251. Total resistance value must not be more than 5 ohms. If the resistance is more than 5 ohms, there is an
open circuit in the ISO 9141 communication network, damage to the DLC C251, damage to the RCM C2041a, or a problem in the in-line connector.
Anti-Lock Brake System (ABS) Module
The ABS module is on the high speed CAN. The ABS module controls the brake pressure to the 4 wheels to keep the vehicle under control while
braking. If one of the bus wires becomes shorted to ground or voltage, communications can continue at a reduced level. Check the high speed CAN
circuits 1908 (WH) and 1909 (BK), between the ABS module C155 and the DLC C251. Total resistance values must not be more than 5 ohms. If the
resistance is more than 5 ohms, there is an open circuit in the high speed CAN, damage to the DLC C251, damage to the ABS module C155, or a
problem in the in-line connector.
Parking Aid Module
The parking aid module is connected to the ISO 9141 communication network. The parking aid module receives input from sensors in the rear bumper
that detect close objects when the transmission is in REVERSE, and the vehicle speed is above 0 km/h (0 mph) and below 8 km/h (5 mph). The ISO
9141 communication network does not function if the wire is shorted to ground or battery voltage. Check the network circuit between the parking aid
module C4014 and the DLC C251. Total resistance value must not be more than 5 ohms. If the resistance is more than 5 ohms, there is an open circuit
in the ISO 9141 communication network, damage to the DLC C251, damage to the parking aid module connector, or a problem in the in-line
connector.
Four-Wheel Drive (4WD) Control Module
The 4WD control module is on the high speed CAN. The 4WD control module regulates the duty cycle to the active torque coupling between FWD
and 4WD when more traction is required. Check the high speed CAN circuits 1908 (WH) and 1909 (BK), between the 4WD control module C3253
and the DLC C251. Total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms, there is an open circuit in the high
speed CAN, damage to the DLC C251, damage to the 4WD control module C3253, or a problem in the in-line connector.
