Information System and Entertainment Systems: Overview Mercury Sable V

Principles of Operation

Note. The smart junction box (SJB) is also known as the generic electronic module (GEM).

Normal Operation

For the sedan, the radio antenna, integral to the rear window glass, receives AM and FM radio waves. The antenna module, which receives voltage from the audio control module (ACM) through circuit CME44 (YE/GN), sends the radio waves to the ACM through the antenna cable.

For the wagon, the fixed radio antenna receives AM and FM radio waves and sends them to the ACM.

The noise suppression equipment reduces engine ignition and electrical systems interference transmitted through the speakers.

1. DTC B2103 (Antenna Not Connected) - sets during the antenna connected test (part of the ACM self-test) when the signal strength is less than the pre-configured threshold value. In order for this DTC to set, the ACM must be tuned to AM, and the self-test must be run with the scan tool.

This pinpoint test is intended to diagnose the following

1. RDS/PTY function setting
2. Wiring, terminals or connectors (sedan only)
3. Antenna
4. Antenna cable
5. Antenna module (sedan only)
6. Charging system
7. Ignition system
8. Noise suppression equipment
9. ACM

The audio control module (ACM) directs audio signals to the speakers and to the rear entertainment module (RETM) (if equipped) in the form of a fluctuating AC voltage. The rear door speakers receive audio signals through the RETM (if equipped) or directly from the ACM.

If the vehicle is equipped with the DVD entertainment system, the RETM mutes the speaker output to the rear speakers when the audio system is in dual-play mode. Make sure the audio system is in single-play mode before diagnosing a symptom of no sound to the rear speakers.

For the navigation system, if the voice guidance setting is set to zero rather than to off, it may appear that the front speakers intermittently produce no sound. Make sure the voice guidance setting is not set to zero before addressing a concern with the front speakers.

1. DTC B2965 (Audio System Speaker Circuit Fault) - sets when an open, a short to ground, or a short to voltage is detected on the front door or rear door speaker circuits. The ACM checks for faults once every 500ms during normal operation. The following should also be noted: The Audiophile ACM does not check for opens in the front door speakers. The navigation ACM does not check for opens.

For some audio systems, a short to ground or short to voltage in the circuitry to one of the speakers will cause all speakers to lose sound due to the built-in overload protection feature of the ACM. In this case, DTC B2965 will set in the ACM, and this pinpoint test should be followed to isolate the damaged circuit.

This pinpoint test is intended to diagnose the following

1. Wiring, terminals or connectors
2. Speaker
3. RETM (if equipped)
4. ACM

The subwoofer speaker is powered by a separate subwoofer amplifier. For wagons, the subwoofer speaker is integral to the subwoofer enclosure. For sedans, there are 2 subwoofer speakers connected to the subwoofer amplifier through circuits VME01 (GN/VT), RME01 (GY), VME02 (VT), and RME02 (YE). The subwoofer receives audio signals from the ACM through circuits VME22 (VT/GN) and RME22 (GN/WH). The subwoofer amplifier receives voltage (at all times) through circuit SBP38 (BN/RD), and ground through circuit GD148 (BK/YE).

To enable the subwoofer amplifier, the ACM sends voltage through the enable/clip circuit SME23 (VT/RD). The circuit acts as both an output (to enable the amplifier) and an input (to detect an amplifier overload condition). A variable resistor in the subwoofer amplifier modifies the voltage signal from the ACM. In the event of an overload, the ACM clips the audio output signal to the amplifier (heard as distortion), in order to prevent damage to the amplifier and speakers.

The clip/enable status is based on the following voltages, as detected by the ACM

1. Less than 0.4 volts: amplifier disabled
2. Between 3.8 and 6.7 volts: amplifier enabled
3. Greater than 8.5 volts: amplifier clipped

An open in circuit SME23 (VT/RD) will cause the subwoofer to produce no sound, because the enable signal will not reach the subwoofer amplifier. A short to ground or short to voltage can cause severe distortion to be heard from the subwoofer.

1. DTC B1154 (Subwoofer #1 Short to Ground) - sets when a short to ground is detected on circuit RME22 (GN/WH) or VME22 (VT/GN). This DTC only sets during the on-demand self-test.
2. DTC B1155 (Subwoofer #1 Short to Battery) - sets when a short to voltage is detected on circuit RME22 (GN/WH) or VME22 (VT/GN). This DTC only sets during the on-demand self-test.
3. DTC B2913 (Audio Subwoofer Not Connected) - sets when the ACM does not detect the subwoofer through circuit SME23 (VT/RD) during the subwoofer connection test (part of the ACM self-test).

This pinpoint test is intended to diagnose the following

1. Fuse
2. Wiring, terminals or connectors
3. Subwoofer amplifier
4. Subwoofer speaker
5. ACM

When the parking aid module (PAM) detects an object in range, it sounds an alarm and grounds circuit CME05 (GN/BU) to the ACM. When the ACM detects the circuit grounded, it reduces the audio output until the parking aid module signal is no longer detected.

1. DTC B2384 (Audio Reverse Park Aid Mute Ckt Failure) - sets during the on-demand test if the mute circuit is detected as active. This could be because the vehicle is in reverse (R) and an object is within range of the parking aid system. Put the vehicle in park (P) while running the on-demand self-test to eliminate this as a possible cause of the DTC.

This pinpoint test is intended to diagnose the following

1. Wiring, terminals or connectors
2. Parking aid system concern

There are 3 different steering wheel controls configurations

1. Non-navigation, without the SYNC system VOL-, VOL+, SEEK-, SEEK+, MEDIA, MUTE
2. Non-navigation, with the SYNC system MENU-, MENU+, VOICE, OK, PHONE
3. Navigation, with or without the SYNC system VOL-, VOL+, SEEK-, SEEK+, MEDIA, VOICE

For vehicles without both navigation and the SYNC system, all the steering wheel controls are wired to the audio control module (ACM). Voltage is sent from the ACM to the steering wheel controls through circuit VME14 (GY/YE), and the ACM ground the reference voltage through circuit RMC27 (WH/BN).

For vehicles with the SYNC system but not navigation, all the steering wheel controls are wired to the accessory protocol interface module (APIM). Voltage is sent from the APIM to the steering wheel controls through circuit CMM15 (GY/BU), and the APIM grounds the reference voltage through circuit CMM14 (WH).

For vehicles equipped with navigation, all the steering wheel controls are wired to the ACM, regardless of whether the vehicle is equipped with the SYNC system or not.

For all configurations, when a switch is pressed, the voltage is routed through a specific resistor value for each function. The ACM (or APIM) then uses the reference voltage to determine which control input function has been selected.

1. DTC B1117 (Audio Steering Wheel Button Stuck) - set by the ACM or the APIM (depending on vehicle configuration) when a steering wheel control switch is detected as active for more than 120 seconds during normal operation, or for any duration during the self-test. A short to ground on VME14 (GY/YE) should not set this DTC, as the reference voltage would fall out-of-range, resulting in DTC B1136 or B2404 being set.
2. DTC B1136 (Audio Steering Wheel Switch #2 Circuit Failure) - set by the APIM when the reference voltage to the steering wheel controls is out-of-range. This can be caused by a number of different failures on the steering wheel controls circuit except for a stuck button or a short to ground in circuit CMM14 (WH).
3. DTC B2404 (Audio Steering Wheel Switch Circuit Fault) - set by the ACM when the reference voltage to the steering wheel controls is out-of-range. This can be caused by a number of different failures on the steering wheel controls circuit except for a stuck button a short to ground in circuit RMC27 (WH/BN).

This pinpoint test is intended to diagnose the following

1. Wiring, terminals or connectors
2. Clockspring
3. Steering wheel controls
4. ACM
5. APIM (if equipped)

The speed sensitive volume function adjusts the volume based on the vehicle speed sensor (VSS) signal from the instrument cluster (IC). The IC does not generate the VSS signal; it gateways the signal from the PCM.

1. DTC U0155 (Lost Communication With Instrument Panel Cluster Control [IC] Module) - sets when the VSS signal is lost for greater than 5 seconds. When the signal is lost, the ACM turns the speed sensitive volume feature off. The smart junction box (SJB) and heating ventilation air conditioning (HVAC) module-electronic automatic temperature control (EATC) also receive this signal, and should demonstrate symptoms if the VSS signal is lost. If no symptoms are present, this DTC can be ignored, as it may have been set by a low battery voltage condition.

This pinpoint test is intended to diagnose the following

1. Speed sensitive volume setting
2. VSS signal concern
3. ACM

The rear entertainment module (RETM) routes audio signals to the audio control module (ACM). In single-play mode, the ACM plays the DVD audio on all speakers. In dual-play mode, the audio to the rear speakers is muted and the RETM continues to control the rear audio source to the headphones.

If the vehicle is equipped with satellite audio and/or the SYNC system, the audio signals from these sources are routed through the RETM to the ACM. This allows for single-play and dual-play to include these audio sources.

This pinpoint test is intended to diagnose the following

1. Wiring, terminals or connectors
2. RETM
3. ACM

Digital signals are received by the satellite antenna and sent to the satellite digital audio receiver system (SDARS) module, which then converts the signals and provides audio signals to the audio control module (ACM), the accessory protocol interface module (APIM), or to the rear entertainment module (RETM), depending on vehicle configuration.

A short to ground typically has no effect on the antenna signal. However, an open in the antenna circuit will result in no sound from the satellite radio system. A short to voltage in the antenna circuit can have varying effects on the system.

1. DTC B1031 (SDARS Satellite Antenna Open) - sets when an open or high resistance is detected in the satellite antenna circuit. This DTC can be either continuous or on-demand.
2. DTC B1032 (SDARS Satellite Antenna Short) - sets when a short to ground is detected in the satellite antenna circuit. This DTC can be either continuous or on-demand.

This pinpoint test is intended to diagnose the following

1. Obstructions to the line of sight
2. Satellite radio antenna cable
3. Satellite radio antenna
4. SDARS module

The satellite digital audio receiver system (SDARS) module receives voltage through circuit SBP03 (BU/RD), and ground through circuit GD103 (BK/BU). Digital signals are received by the satellite radio antenna and sent to the SDARS module, which converts the signals to analog and sends them to either the audio control module (ACM) or to the accessory protocol interface module (APIM) (if equipped).

If there is an open in the satellite antenna circuit, there will be no satellite audio. The ACM display will indicate a satellite antenna concern (the method varies according to the type of ACM) when the audio system is operated in satellite radio mode. To diagnose an open in the satellite antenna circuit, go to Pinpoint Test H .

The SDARS module transmits left and right channel audio signals. When there is a fault in any of the audio signal circuits, the audio quality is reduced. If the circuits for a specific channel are shorted together, loss of audio on the entire channel will occur. This can be detected by using the SDARS module tones test.

1. DTC U0184 (Lost Communication With Radio [ACM]) - set by the SDARS module when certain medium speed controller area network (MS-CAN) messages are missing from the ACM for greater than 5 seconds. This results in loss of satellite radio functionality.
2. DTC U0193 (Lost Communication With Digital Audio Control Module [SDARS]) - set by the ACM when certain MS-CAN messages are missing from the SDARS module for greater than 5 seconds. This results in loss of satellite radio functionality.
3. DTC U0197 (Lost Communication With Telephone Control Module) - set by the SDARS module when certain MS-CAN messages are missing from the APIM for greater than 5 seconds.

This pinpoint test is intended to diagnose the following

1. Subscription status
2. Wiring, terminals or connectors
3. SDARS module
4. APIM (if equipped)
5. ACM

The satellite digital audio receiver system (SDARS) module receives voltage through circuit SBP03 (BU/RD) and ground through circuit GD103 (BK/BU). Digital signals are received by the satellite radio antenna and sent to the SDARS module, which converts the signals to analog and sends them to either the rear entertainment module (RETM), or the accessory protocol interface module (APIM) (if equipped).

The satellite audio signals utilize separate circuitry from the remaining audio signals. This allows the audio control module (ACM) to distinguish between satellite and SYNC or DVD audio, in order to provide for more dual-play options.

If there is an open in the satellite radio antenna circuit, there will be no satellite audio. The ACM display will indicate a satellite antenna concern (the method varies according to the type of ACM) when the audio system is operated in satellite radio mode. To diagnose an open in the satellite radio antenna circuit, go to Pinpoint Test H .

This pinpoint test is intended to diagnose the following

1. Subscription status
2. Wiring, terminals or connectors
3. SDARS module
4. RETM
5. APIM (if equipped)
6. ACM

Normal Operation - Vehicles Without the SYNC System

Audio signals are sent from the audio input jack to the audio control module (ACM). There are no external power or ground circuits to the audio input jack.

The global positioning system (GPS) antenna provides information from the GPS satellite system to the GPS receiver in the navigation audio control module (ACM). This information is used to calculate vehicle position and direction of travel.

1. DTC 2204 (GPS Antenna Connection Open or Short) - sets when an open, short to ground, or short to voltage is detected in the GPS antenna circuit.

This pinpoint test is intended to diagnose the following

1. GPS antenna
2. Audio control module (ACM)

Scheme 1

1. L1 CHECK THE OPERATION OF THE GPS ICON Move the vehicle outside of any enclosed structure to an area that is unobstructed by trees, tall buildings, and bridges. Operate the audio system in navigation mode. Does the GPS icon appear, then disappear? YES : The system is operating correctly at this time. NOTIFY the customer that obstructions to the line of sight may affect the GPS antenna. NO : Go to L2 .
2. L2 CHECK THE ACM RECORDED DTCs Check the recorded DTCs from the ACM self-test. Is DTC B2204 recorded? YES : Go to L4 . NO : Go to L3 .
3. L3 CHECK THE GPS ANTENNA MOUNTING Verify the GPS antenna is installed correctly and no aftermarket equipment is obstructing the antenna. Is the GPS antenna mounted correctly? YES : Go to L4 . NO : Correctly INSTALL the GPS antenna. REFER to «Global Positioning System (GPS) Antenna»(ref-293482-S11780009302008080700000) . TEST the system for normal operation.
4. L4 SUBSTITUTE THE GPS ANTENNA Install a known good GPS antenna. Move the vehicle outside of any enclosed structure to an area that is unobstructed by trees, tall buildings, and bridges. Operate the audio system in navigation mode. Does the GPS icon appear, then disappear? YES : INSTALL a new GPS antenna. REFER to «Global Positioning System (GPS) Antenna»(ref-293482-S11780009302008080700000) . CLEAR the DTCs. REPEAT the self-test. NO : INSTALL the original GPS antenna. Go to L5 .
5. L5 CHECK FOR CORRECT ACM OPERATION Disconnect all the ACM connectors. Check for: corrosion damaged pins pushed-out pins Connect all the ACM connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? YES : INSTALL a new ACM. REFER to «Audio Control Module (ACM)»(ref-293482-S38570490942008080700000) . TEST the system for normal operation. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

The audible switch feedback settings are controlled by the audio control module (ACM). The audible switch feedback can be set to ALL, TOUCH SCREEN, or NONE, depending on user preference.

This pinpoint test is intended to diagnose the following

1. Audible switch feedback setting
2. ACM

Scheme 2

1. M1 CHECK THE SWITCH DISPLAY Key in ON position. Turn the ACM on. Press the MENU button. Select the FEEDBACK tab. Is NONE highlighted on the audible feedback settings? YES : SELECT "ALL BUTTONS". TEST the system for normal operation. NO : Go to M2 .
2. M2 CHECK FOR CORRECT ACM OPERATION Disconnect all the ACM connectors. Check for: corrosion damaged pins pushed-out pins Connect all the ACM connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? YES : INSTALL a new ACM. REFER to «Audio Control Module (ACM)»(ref-293482-S38570490942008080700000) . TEST the system for normal operation. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

The voice guidance settings are controlled by the audio control module (ACM). The voice guidance volume can be adjusted or turned off depending on user preference.

This pinpoint test is intended to diagnose the following

1. Incorrect system setting
2. ACM

The primary source of vehicle location for the navigation system is the audio control module (ACM) receiving the position signal through the global positioning system (GPS) antenna.

In addition, the ACM receives the wheel pulse signal from the instrument cluster (IC) (which gateways the signal from the ABS module). This secondary signal is used to calculate vehicle position when the GPS signal is lost. It also supports the adaptive learning function of the ACM, whereby the ACM can compensate for long-term differences between the GPS signal location, and the actual distance traveled by the vehicle.

1. DTC B2204 (GPS Antenna Connection Open or Short) - sets when an open, short to ground, or short to voltage is detected in the GPS antenna circuit. If DTC B2204 is present, go to «Pinpoint Test L»(ref-293482-S04208796652008080700000) .
2. DTC U0155 (Lost Communication With Instrument Panel Cluster [IC] Control Module) - sets when the ACM is missing messages from the instrument cluster for greater than 5 seconds.
3. DTC U2473 (Unexpected Vehicle Speed [VSS]) - sets when the calculated vehicle distance traveled based on the wheel pulse signal does not agree with the GPS antenna location. To do this, the ACM compares the wheel pulse signal during a 4-second range, and compares it with the change in GPS antenna location. If the ACM finds that the variation is greater than 0.5% after performing this check 4 times, it sets DTC U2473. When DTC U2473 is set, the adaptive learn function is disabled. This DTC is also set when the navigation rolling wheel count signal is missing for greater than 2 seconds with the key in RUN.

This pinpoint test is intended to diagnose the following

1. GPS antenna
2. VSS signal concern
3. ACM

When the VOICE button (an icon of someone speaking) is pressed, the audio control module (ACM) detects the change in reference voltage on circuit VME14 (GY/YE) and enters voice recognition mode. A microphone located in the interior rear view mirror receives the voice command and sends a signal to the ACM through circuits VMN02 (WH/BN) and RMN02 (VT/BN). Power to the interior rear view mirror is provided through circuit CBP41 (BU), and ground through circuit GD133 (BK).

The microphone test is available through the integrated diagnostic system (IDS). Running this test causes the ACM to produce a test tone. If the system is operating correctly, the microphone detects the tone and produces a signal to the ACM indicating the tone was heard.

1. DTC B2633 (Driver-Front Microphone Circuit Failure) - set by the ACM during the microphone test when the ACM does not receive an adequate signal from the microphone when the test tone is sounded.

This pinpoint test is intended to diagnose the following

1. Fuse
2. Wiring, terminals or connectors
3. Steering wheel controls
4. Microphone (part of the interior rear view mirror)
5. ACM

The accessory protocol interface module (APIM) receives voltage at all times from circuit SBP03 (BU/RD), and ground through circuit GD103 (BK/BU). The wake-up signal is sent to the APIM by the audio control module (ACM) via the medium speed controller area network (MS-CAN).

1. DTC U0184 (Lost Communication With Radio [ACM]) - set by the APIM when it is missing messages from the ACM over the MS-CAN for greater than 5 seconds.
2. DTC U0196 (Lost Communication With Entertainment Control Module - Rear [AUX]) - set by the APIM when it is missing messages from the RETM over the MS-CAN for greater than 5 seconds.
3. DTC U0197 (Lost Communication With Telephone Control Module) - set by the ACM when it is missing messages from the APIM over the MS-CAN for greater than 5 seconds.

This pinpoint test is intended to diagnose the following

1. Audio system concern
2. Communication network concern
3. Customer error
4. Customer device
5. APIM
6. ACM

When a new Bluetooth® device is added, the accessory protocol interface module (APIM) and the Bluetooth® device must be paired together. Most Bluetooth® devices will pair with the SYNC system, although functionality will vary. To determine if a Bluetooth® device is supported, retrieve the consumer interface processor (CIP) software level using the Accessory Protocol Interface Module (APIM) Software Level Check , and verify the customer device is on the compatibility list for the current CIP software level.

Pairing a Bluetooth® device is accomplished through the "Add Device" selection of the phone menu. When pairing a device, the SYNC system generates a unique personal identification number (PIN) that must be entered on the Bluetooth® device in order for the pairing process to be successful. There are also some device-specific actions that must take place. For additional information on the pairing process, refer to the Owner's Literature.

This pinpoint test is intended to diagnose the following

1. Incompatible Bluetooth® device
2. Customer error
3. Customer Bluetooth® device
4. APIM

The universal serial bus (USB) port is connected to the accessory protocol interface module (APIM) through the USB cable. The USB port can be used to play audio files or upload software from mass storage devices, or for connecting a media device.

If supported by the user device, the USB can provide charging. Because of this feature, when a USB device is plugged into the USB port, the SYNC system does not automatically switch to the device.

The USB cable and port are not serviceable separately.

1. DTC U261C (USB #1 Device Error) - sets when the APIM detect an over-current or over-temperature condition in the USB circuit. This can be caused by a fault in the USB cable or port, or by the customer USB device.

This pinpoint test is intended to diagnose the following

1. Customer USB device
2. USB cable and port
3. APIM

The text-to-speech (TTS) and voice prompt features speak certain text information and interaction requests in order to minimize driver distraction by having to look at the audio control module (ACM) while driving. The ring tone alerts the driver to an incoming call.

Audible prompts can range from a simple tone to more elaborate spoken text, based on the customer setting. When interaction mode is set to standard, detailed guidance is provided. When interaction mode is set to advanced, most prompts are tones only and minimal audible guidance is provided. Refer to the Owner's Literature for further information on voice interaction.

The audio signals for the TTS and voice prompt features, the ring tones, and audio from the outside device during a phone call, are sent from the accessory protocol interface module (APIM) to the ACM through circuits VMN14 (WH/VT) and RMN14 (GY/BN).

This pinpoint test is intended to diagnose the following

1. Customer setting
2. Wiring, terminals or connectors
3. ACM
4. APIM

The accessory protocol interface module (APIM) sends left and right channel analog audio signals through circuits VME41 (GN/OG), RME41 (BU/BN), VME42 (VT/BN), and RME42 (YE/BU). If the vehicle is equipped with a DVD entertainment system, these audio signals are sent to the rear entertainment module (RETM), then to the audio control module (ACM). In vehicles without a DVD entertainment system, the audio signals are sent directly to the ACM.

This pinpoint test is intended to diagnose the following

1. Wiring, terminals or connectors
2. RETM (if equipped)
3. ACM
4. APIM

When the VOICE button (represented by an icon of someone speaking) is pressed, it changes the reference voltage on circuit VME54 (BU/OG), and the audio system enters voice recognition mode. If the vehicle is equipped with navigation, the VOICE switch is wired to the audio control module (ACM). If the vehicle is not equipped with navigation, the VOICE switch is wired to the accessory protocol interface module (APIM). A microphone located in the interior rear view mirror receives the voice command and sends a signal to the APIM through circuits VMN02 (WH/BN) and RMN02 (VT/BN). The microphone is also used to detect outgoing audio during a phone call.

If the vehicle is equipped with navigation, the APIM receives the microphone input, and also broadcasts it to the ACM through circuits VMN02 (WH/BN) and RMN02 (VT/BN). This is to allow voice commands specific to the navigation system to be handled directly by the ACM. The first voice commands spoken determine which system handles the voice commands.

1. DTC B1038 (Microphone Input Circuit Failure) - set by the APIM during the on-demand self-test if the APIM does not detect the microphone.
2. DTC B2633 (Driver-Front Microphone Circuit Failure) - set by the ACM during the microphone test when the ACM does not receive an adequate signal from the microphone when the test tone is sounded.

This pinpoint test is intended to diagnose the following

1. Fuse
2. Wiring, terminals or connectors
3. Steering wheel controls
4. Microphone (part of the interior rear view mirror)
5. ACM (if equipped with navigation)
6. APIM