Ford Galaxy / Ford S-MAX. Manual — part 803

The generic electronic module (GEM) knows which modules are in the Controller Area
Network (CAN) and checks whether all modules are communicating. If a module is not
communicating a trouble code (DTC) is set in the GEM. There is a trouble code (DTC) for
every module.

Faulty communications

If the Controller Area Network (CAN) is in operation then the generic electronic module
(GEM) continuously monitors the flow of information in the network. If the GEM determines
that, for some reason, the communications in the CAN bus are interrupted, it can set a
trouble code (DTC). The GEM has trouble codes for all parts of the CAN bus (one each for
the HS CAN bus and the MS/MM CAN bus).

With the exception of the GEM, which only knows one type of DTC, each module uses two
types of DTC in relation to communication faults. These are:

Faulty messages
Faulty configuration

As the GEM is the main module in the network, it does not have a DTC for faulty
configuration.

Faulty messages

The control modules continuously monitor the flow of information in the Controller Area
Network (CAN). If a module receives a message it cannot interpret it sends a fault message
via the CAN bus. The modules also have function which allows them to detect any faulty
messages they generate themselves. This prevents interference on the CAN bus. If there is
a lot of interference in the network then any modules which cannot communicate properly
can switch themselves off. This status is referred to as "databus OFF" - the module can no
longer send or receive information.

To prevent the vehicle from coming to a sudden standstill or suffering a total loss of
particular functions if a fault occurs in the CAN bus, certain modules have an emergency
running mode. This means that modules which are required for driving or for safety aspects
(e.g. the powertrain control module (PCM) or the transmission control module (TCM)) can
maintain a restricted functionality on the basis of predefined or estimated data. For
example, if communications to the transmission control module (TCM) are interrupted then
the transmission will use a preselected gear which will enable the customer to at least drive
to the nearest workshop. A module remains in "databus OFF" mode until the power supply
to the module is switched off. If the power supply is reconnected the module attempts to
re-establish communications.

Faulty configuration

The generic electronic module (GEM) transmits its configuration ID within the messages it
sends out to other modules. To enable the modules in the Controller Area Network (CAN) to
communicate with each other they must have the same configuration ID, as modules only
look at messages carrying their own configuration ID. If the signal configuration of a
module does not match the signal configuration of the GEM then a trouble code (DTC) is
stored in the module with the faulty configuration.

NOTE: A module will save a trouble code (DTC) if it does not receive any messages from
the generic electronic module (GEM). This also applies if there are any software errors in
the module. If the circuit in the Controller Area Network (CAN) is interrupted then certain
modules will also not receive any messages from the GEM.

Local Interconnect Network (LIN)

The Local Interconnect Network (LIN) bus is a standard which has been developed for cost-
effective communications between intelligent sensors and actuators in motor vehicles. LIN
is used wherever the bandwidth and versatility of CAN is not required.

The LIN specification comprises the LIN protocol, a standard format for describing a

complete LIN network and the interface between a LIN network and the application.

A LIN network is made up of a LIN master and one or more LIN slaves.

The LIN network utilizes the master/slave principle for the purpose of bus access control.
This has the significant advantage that few resources (CPU performance, ROM, RAM) are
required for bus management in the slave module. The master is implemented in a control
module or a gateway which has the necessary resources. All communication is initiated by
the master. Consequently, a message always consists of a header, which is generated by
the master, and a response from the slave.

The data transfer rate is in the region of up to 20 Kbit/s.

The LIN master knows the time sequence of all data which are to be transmitted. These
data are transmitted by the corresponding LIN slaves (e.g. ultrasonic sensors) when
requested to do so by the LIN master.

LIN is a single-wire bus, i.e. the data are transmitted across a single-stranded cable.
Usually the same cable is also used to provide the supply voltage. The ground connection of
the supply voltage also acts as the ground connection of the data transmission. No
terminating resistors are used in the LIN network.

Module Communications Network -
Communications Network

S-MAX/Galaxy 2006.5 (02/2006-)

Print

Diagnosis and Testing

Special Tool(s)

General Equipment

Inspection and Testing

1. 1. CHECK the concern.

2. 2. Visually CHECK for any obvious mechanical or electrical damage.

Visual Inspection

3. 3. RECTIFY any obvious causes for a concern found during the visual inspection

before performing any further tests. CHECK the operation of the system.

4. 4. If the concern persists after the visual inspection, PERFORM a fault diagnosis with

the

Ford approved diagnostic tool

and RECTIFY any displayed faults in accordance

with the displayed fault description. CHECK the operation of the system.

5. 5. On a vehicle without stored fault(s), PROCEED according to the Symptom Chart

and the corresponding symptom.

6. 6. After testing or rectifying the fault and after completion of operations, READ OUT

the fault memories of all vehicle modules and DELETE any stored faults. READ OUT
all fault memories again after a road test.

Diagnostic Trouble Code (DTC) Table - Generic Electronic Module (GEM)

Terminal Probe Kit

29-011A

Digital Multimeter
Ford approved diagnostic tool

Electrical

Fuse(s).
Wiring harness.
Electrical connectors.

DTC

Description

Action

B1131-

88

No communications possible with the wiper motor module.

GO to Pinpoint
Test

T.

U0155-

00

No communications possible with the instrument cluster.

GO to Pinpoint
Test

AH.

U0129-

00

No communication with the anti-block brake system module.

GO to Pinpoint
Test

AC.

U0100-

00

No communications possible with the powertrain control module
(PCM).

GO to Pinpoint
Test

AG.

B112B-

88

No communications possible with the steering wheel module.

GO to Pinpoint
Test

O.

B112C-

88

No communications possible with the interior monitoring sensor.

GO to Pinpoint
Test

AA.

Symptom Chart

B1D17-

88

No communications possible with the anti-theft alarm signal horn
with integrated battery.

GO to Pinpoint
Test

Z.

U0231-

00

No communications possible with the rain sensor/light sensor.

GO to Pinpoint
Test

S.

B1130-

88

No communications possible with the light switch unit.

GO to Pinpoint
Test

U.

U0214-

00

No communications possible with the keyless vehicle module.

GO to Pinpoint
Test

J.

U0104-

00

No communications possible with the collision warning module.

GO to Pinpoint
Test

P.

U0001-

00

No communications possible via the HS CAN bus.

GO to Pinpoint
Test

AK.

U0010-

00

No communications possible via the MS CAN bus.

GO to Pinpoint
Test

AJ.

Symptom

Possible Sources

Action

Driver's side door module not communicating
with the Ford approved diagnostic tool

Fuse(s)
Circuit(s)
Driver's side door module

*
*
*

GO to

Pinpoint
Test

A.

*

Passenger side door module not communicating
with the Ford approved diagnostic tool

Fuse(s)
Circuit(s)
Passenger's side door module

*
*
*

GO to

Pinpoint
Test

B.

*

Navigation system touch screen not
communicating with the Ford approved
diagnostic tool - vehicles equipped with DVD
navigation system with touch screen

Fuse(s)
Circuit(s)
Navigation system touch

screen

*
*
*

GO to

Pinpoint
Test

G.

*

DVD drive not communicating with the Ford
approved diagnostic tool - vehicles equipped with
DVD navigation system with touch screen

Fuse(s)
Circuit(s)
DVD drive

*
*
*

GO to

Pinpoint
Test

H.

*

Fuel-fired booster heater/programmable fuel-
fired booster heater not communicating with the
Ford approved diagnostic tool

Fuse(s)
Circuit(s)
Fuel fired booster

heater /programmable fuel
fired booster heater

*
*
*

GO to

Pinpoint
Test

I.

*

Keyless vehicle module not communicating with
the Ford approved diagnostic tool

Fuse(s)
Circuit(s)
Keyless vehicle module

*
*
*

GO to

Pinpoint
Test

J.

*

Auxiliary climate control module not
communicating with the Ford approved
diagnostic tool

Fuse(s)
Circuit(s)
Auxiliary climate control

module

*
*
*

GO to

Pinpoint
Test

K.

*

Rain sensor/light sensor not communicating with
the generic electronic module (GEM)

Fuse(s)
Circuit(s)
Rain sensor/light sensor

*
*
*

GO to

Pinpoint
Test

S.

*

Wiper motor module not communicating with the
generic electronic module (GEM)

Fuse(s)
Circuit(s)
Wiper motor module

*
*
*

GO to

Pinpoint
Test

T.

*

Light switch unit not communicating with the
generic electronic module (GEM)

Fuse(s)
Circuit(s)
Light switch unit

*
*
*

GO to

Pinpoint
Test

U.

*

Remote control/tire pressure monitoring receiver
module not communicating with the generic
electronic module (GEM)

Fuse(s)
Circuit(s)
Remote control/tire pressure

monitoring receiver module

*
*
*

GO to

Pinpoint
Test

V.

*

Driver's side rear door module not
communicating with the driver's side door
module

Fuse(s)
Circuit(s)
Driver's side rear door module

*
*
*

GO to

Pinpoint
Test

W.

*