Computer/Integrating Systems Schematic Icons Icon Icon Definition CAUTION: When performing service on or near the SIR components or the SIR wiring, the SIR system must be disabled. Refer to SIR Disabling and Enabling Zones. Failure to observe the correct procedure could cause deployment of the SIR components, personal injury, or unnecessary SIR system repairs. IMPORTANT: Twisted-pair wires provide an effective shield that helps protect sensitive electronic components from electrical interference. In order to prevent electrical interference from degrading the performance of the connected components, you must maintain the proper specification when making any repairs to the twisted-pair wires shown : The wires must be twisted a minimum of 9 turns per 31 cm (12 in) as measured anywhere along the length of the wires. The outside diameter of the twisted wires must not exceed 6.0 mm (0.25 in)
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Scheme 17
| Callout | Component Name |
|---|---|
| 1 | I/P Carrier |
| 2 | I/P Side Panel - Left |
| 3 | Data Link Connector (DLC) |
| 4 | Courtesy Lamp - Left Footwell |
| 5 | Fuse Box Steering Column |
Scheme 18
| Callout | Component Name |
|---|---|
| 1 | I/P Cluster Trim |
| 2 | I/P Carrier Trim |
| 3 | Instrument Panel Module (IPM) |
| 4 | Knee Bolster |
Scheme 19
| Callout | Component Name |
|---|---|
| 1 | Module Bracket Assembly |
| 2 | Remote Control Door Lock Receiver (RCDLR) |
| 3 | Rear Integration Module (RIM) |
| 4 | Rear Object Sensor Control Module |
| 5 | Rear Window Shelf |
Scheme 20
| Callout | Component Name |
|---|---|
| 1 | Splice Pack SP300 |
| 2 | G307 |
| 3 | LF Floor Panel |
Data Link Connector (DLC) Connector End Connector Part Information OEM: 511161601 Service: Pin Wire Color Circuit No. Function 1 D-GN 5060 Low Speed GMLAN Serial Data 2-3 - - Not Used 4 BK 350 Ground 5 BK/WH 351 Ground 6 TN/BK 2500 High Speed GMLAN Serial Data (+) (1) 7-13 - - Not Used 14 TN 2501 High Speed GMLAN Serial Data (-) (1) 15 - - Not Used 16 RD/WH 1140 Battery Positive Voltage Terminal Part Information Terminal: Terminal Seal: Release Tool: Core Crimp: Insulation Crimp: Test Probe
Instrument Panel Module (IPM) - C1 Connector End Connector Part Information OEM: 1318757-1 Service: 26-Way M 90 Series (WH) Pin Wire Color Circuit No. Function 1 YE 32 Instrument Panel Lamp Fuse Supply Voltage (1) 2 YE 1491 Backlight Lamp Control 3 YE 6817 LED Backlight Dimming Control YE 6817 4 - - Not Used 5 WH 17 Stop Lamp Switch Signal 6 PK 3 Run/Crank Ignition 1 Voltage 7 - - Not Used 8 YE/BK 5728 ECM/TCM Serial Data Wake Up 9 YE 5727 High Speed GMLAN Serial Data Wake Up 10 PK 5722 Ignition Mode Switch LED Supply Voltage 11 D-GN 5525 Tap Up/Tap Down Enable Signal 12 WH 111 Hazard Switch Signal 13 BN 1356 Flash To Pass Switch Signal 14 BN/WH 301 Park Lamp Switch On Signal 15 L-GN 5724 Ignition Mode Switch Mode Control 16 D-BU 5719 Ignition Mode Switch Start LED Signal 17 L-GN 5720 Ignition Mode Switch Accessory LED Signal 19 L-BU 6857 Headlamp Automatic High Beam Dim Status 20 L-BU 1134 Park Brake Switch Signal 21 PK/BK 1597 Interior Lamp Switch On Signal 22 PU 1783 Twilight Sentinel Delay Signal 23 WH 103 Headlamp Switch On Signal 24 - - Not Used 25 PU 1375 Remote Radio Control Head Accessory Supply Voltage 26 OG 5721 Ignition Mode Switch Off LED Signal Terminal Part Information Terminal: Terminal Seal: Release Tool: Core Crimp: Insulation Crimp: Test Probe
Instrument Panel Module (IPM) - C2 Connector End Connector Part Information OEM: 1318756-1 Service: 24-Way M TYCO (WH) Pin Wire Color Circuit No. Function 1 BN 4 Accessory Voltage 2 YE 6847 Shift Select Switch Park Supply Voltage 3 D-GN/WH 1317 Fog Lamp Relay Control 4 TN/WH 1969 Headlamp High Beam Relay Control 5 WH 1080 Park Lamp Relay Control 6 PK/WH 1970 Headlamp Low Beam Relay Control 7 OG 300 Run Ignition 3 Voltage 8 - - Not Used 9 TN 28 Horn Relay Control 10 TN 28 Horn Relay Control 11 GY 478 Windshield Wiper Switch Signal (2) 12 BN 253 Trunk Release Relay Control 13 GY 2096 Steering Column Tilt and Telescope Up Switch Signal 14 YE 2097 Steering Column Tilt and Telescope Down Switch Signal 15 D-BU 6856 Headlamp Automatic High Beam Dim Enable 16 WH 5741 Steering Column Lock Module Lock Enable Relay Control 17-18 - - Not Used 19 D-GN/WH 1932 Shift Select Switch Park Signal 20 WH 1538 Headlamp On With Wipers Signal 21 PK 2094 Steering Column Tilt and Telescope Forward Switch Signal 22 OG 2095 Steering Column Tilt and Telescope Rearward Switch Signal 23 D-GN 1399 RAP Relay Coil Supply Voltage 24 WH 2282 Headlamp Washer Relay Control Terminal Part Information Terminal: Terminal Seal: Release Tool: Core Crimp: Insulation Crimp: Test Probe
Instrument Panel Module (IPM) - C3 Connector End Connector Part Information OEM: 1318758-1 Service: 30-Way M AMP Hybrid (WH) Pin Wire Color Circuit No. Function 1 RD/WH 1140 Battery Positive Voltage 2 RD/WH 3340 Battery Positive Voltage 3 BK/WH 151 Signal Ground 4 TN 2501 High Speed GMLAN Serial Data (-) (1) 5 TN/BK 2500 High Speed GMLAN Serial Data (+) (1) 6 D-GN 44 Instrument Panel Lamp Dimmer Switch Signal 7 PK 5076 Current Sensor Supply Voltage 8 WH 5075 Current Sensor Signal 9 BN 5077 Current Sensor Low Reference 10 BK/WH 451 Signal Ground 11 L-BU 187 Rear Fog Lamp Switch Signal 12 OG 192 Front Fog Lamp Switch Signal 13 L-BU/WH 1414 Left Front Turn Signal Switch Signal 14 TN/WH 99 Windshield Washer Fluid Level Sensor Signal 15 TN 2501 High Speed GMLAN Serial Data (-) (1) 16 TN/BK 2500 High Speed GMLAN Serial Data (+) (1) 17 BN 5360 Brake Apply Sensor Low Reference 18 D-BU 1796 Steering Column Radio Control Signal 19 L-BU/BK 1688 5 Volt Reference 20 GY 1884 Cruise Control Set/Coast/Resume/Accelerate Switch Signal 21 D-GN 5060 Low Speed GMLAN Serial Data 22 D-GN 5060 Low Speed GMLAN Serial Data 23 - - Not Used 24 L-BU 1485 Flash To Pass Switch Supply Voltage 25 D-BU/WH 1415 Right Front Turn Signal Switch Signal 26 BN/WH 1571 Traction Control Switch Signal (2) 27 WH 5359 Brake Apply Sensor Supply Voltage 28 YE 5361 Brake Apply Sensor Signal 29 L-GN/WH 5723 Ignition Mode Switch Mode Voltage 30 - - Not Used Terminal Part Information Terminal: Terminal Seal: Release Tool: Core Crimp: Insulation Crimp: Test Probe
Rear Integration Module (RIM) - C1 Connector End Connector Part Information OEM: 174046-2 Service: 16-Way F 40 Series Multi Lock (BK) Pin Wire Color Circuit No. Function 1 D-GN 646 Reverse Relay Coil Feed 2 D-BU 1393 Courtesy Lamp Relay Coil Control 3 WH 193 Rear Defog Relay Control 4 TN 755 RAP Relay Coil Control 5-9 - - Not Used 10 YE 1977 Rear Fog Lamp Relay Control (Export) 11 L-BU 1344 Trunk Release Relay Output-Coil 12 BN/WH 1429 Standing Lamp Relay Feed 13-16 - - Not Used Terminal Part Information Terminal: Terminal Seal: Release Tool: Core Crimp: Insulation Crimp: Test Probe
Rear Integration Module (RIM) - C2 Connector End Connector Part Information OEM: 174047-2 Service: 20-Way M Hinged Lock (BK) Pin Wire Color Circuit No. Function 1 - - Not Used 2 PK 1339 Run/Crank Ignition 1 Voltage 3 YE/BK 1334 Left Rear Turn Signal Lamp Supply Voltage 4 - - Not Used 5 L-BU 2380 Rear Parking Assist Chime Signal 6-8 - - Not Used 9 YE 5530 Hood Open Switch Signal 10 GY 112 Windshield Wiper Switch Low/Pulse Signal (Export) 11 YE 5058 Intrusion Sensor Armed Signal (Export) 12 TN/BK 5168 Power Sounder Enable Signal (Export) 13 D-GN/WH 1335 Right Rear Turn Signal Lamp Supply Voltage 14 PU 5531 Hood Closed Switch Signal 15-16 - - Not Used 17 D-BU/WH 149 Courtesy Lamp Supply Voltage 18 - - Not Used 19 OG/BK 744 Trunk Ajar Switch Signal 20 PU 5059 Intrusion Sensor Alarm On Signal (Export) Terminal Part Information Terminal: Terminal Seal: Release Tool: Core Crimp: Insulation Crimp: Test Probe
Rear Integration Module (RIM) - C3 Connector End Connector Part Information OEM: 174045-2 Service: 12-Way M 40 Series Multi Lock (BK) Pin Wire Color Circuit No. Function 1 D-BU/WH 1315 Right Front Turn Signal Lamp Supply Voltage 2 L-BU/WH 1314 Left Front Turn Signal Lamp Supply Voltage 3 - - Not Used 4 RD/BK 542 Battery Positive Voltage 5-9 - - Not Used 10 D-GN 5060 Low Speed GMLAN Serial Data 11 - - Not Used 12 YE 18 Left Rear Stop/Turn Lamp Supply Voltage Terminal Part Information Terminal: Terminal Seal: Release Tool: Core Crimp: Insulation Crimp: Test Probe
Rear Integration Module (RIM) - C4 Connector End Connector Part Information OEM: 173850-1 Service: 8-Way F 070 (WH) Pin Wire Color Circuit No. Function 1 - - Not Used 2 RD/BK 442 Battery Positive Voltage 3 GY 157 Interior Lamp Control 4 BK/WH 851 Signal Ground 5 YE 18 Left Rear Stop/Turn Lamp Supply Voltage 6 D-GN 19 Right Rear Stop/Turn Lamp Supply Voltage 7 RD/WH 540 Battery Positive Voltage 8 BK 850 Ground Terminal Part Information Terminal: Terminal Seal: Release Tool: Core Crimp: Insulation Crimp: Test Probe
Begin the system diagnosis with Diagnostic System Check - Vehicle in Vehicle DTC Information. The Diagnostic System Check - Vehicle will provide the following information
- The identification of the control modules which are not communicating.
- The identification of any stored diagnostic trouble codes (DTCs) and their status.
The use of the Diagnostic System Check - Vehicle will identify the correct procedures to begin vehicle diagnosis. These must be performed before system DTC or symptom diagnosis.
Test Description
The number below refers to the step number on the diagnostic table.
- 4: If the battery positive voltage and ground circuits of the DLC are functioning properly, the malfunction must be due to the scan tool.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Data Link Connector (DLC) Schematics Connector End View Reference: Computer/Integrating Systems Connector End Views | |||
| 1 | Test the battery positive voltage circuit of the data link connector (DLC) for an open or a short to ground. Refer to the following procedures in Wiring Systems: Circuit Testing Wiring Repairs Did you find and correct the condition? | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | Go to Step 2 |
| 2 | Test the ground circuits of the DLC for an open or high resistance. Refer to the following procedures in Wiring Systems: Circuit Testing Wiring Repairs Did you find and correct the condition? | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | Go to Step 3 |
| 3 | Inspect for poor connections and terminal tension at the DLC. Refer to the following procedures in Wiring Systems: Testing for Intermittent Conditions and Poor Connections Connector Repairs Did you find and correct the condition? | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | Go to Step 4 |
| 4 | The scan tool may be malfunctioning. Refer to the scan tool user guide. Did you obtain a properly operating scan tool? | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | |
Scan Tool Does Not Power Up
The numbers below refer to the step numbers on the diagnostic table.
- 2: A partial malfunction in the high speed GMLAN serial data circuits uses a different procedure from a total malfunction of the high speed GMLAN data circuits. The scan tool communicates with the following modules on the high speed GMLAN serial data circuits: Distance sensing cruise control (DSCC) module Instrument panel module (IPM) Electronic brake control module (EBCM) Electronic suspension control (ESC) module Engine control module (ECM) Transmission control module (TCM)
- 8: Data link connector (DLC) terminals 6 and 14 provide the connection to the GMLAN serial data high circuit and the GMLAN serial data low circuit respectively.
- 15: If only one of the high speed GMLAN circuits is open all communication on the high speed bus will be disrupted.
- 19: The communication malfunction may have prevented diagnosis of the customer complaint.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Data Link Connector (DLC) Schematics Connector End View Reference: Master Electrical Component List in Wiring Systems | |||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | IMPORTANT: Make sure the CANdi module works fine. When functioning properly, CANdi's LED flashes. In the event of a problem, the LED will be constantly illuminated. Turn ON the ignition, with the engine OFF. Perform the Vehicle DTC Information function on the scan tool, under Computer/Integrating Systems. Does the scan tool communicate with any module on the GMLAN serial data circuits? | Go to Step 3 | Go to Step 6 |
| 3 | Did you record any DTCs in the range of U2105-U2199? | Go to DTC U2105-U2199 | Go to Step 4 |
| 4 | Did you record any DTCs in the range of U0100-U0299? | Go to DTC U0100-U0299 | Go to Step 5 |
| 5 | IMPORTANT: Turn ON the ignition, with the engine OFF, when testing for a short to voltage. Use the DMM MIN/MAX function to capture intermittent conditions. Disconnect the scan tool from the data link connector (DLC). Test the high speed GMLAN serial data circuits for: An intermittent short to ground An intermittent short to voltage An intermittent short between them An intermittent open on any of the circuits Refer to the following in Wiring Systems: Testing for Intermittent Conditions and Poor Connections Circuit Testing Connector Repairs GMLAN Wiring Repairs Did you find and correct the condition? | Go to Step 21 | Go to Diagnostic Aids |
| 6 | Disconnect the instrument panel module (IPM). Test the following circuits of the IPM for an open or short to ground: The battery positive voltage input circuits The battery positive voltage output circuits The ignition mode switch input circuits The switched battery positive voltage circuits Refer to Circuit Testing and Wiring Repairs in Wiring Systems.Did you find and correct the condition? | Go to Step 18 | Go to Step 7 |
| 7 | Test the ground circuits of the IPM for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 18 | Go to Step 8 |
| 8 | Inspect for poor connections at the DLC terminals 6 and 14. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 18 | Go to Step 9 |
| 9 | Test the high speed GMLAN serial data circuits between the IPM and DLC for: A short to ground A short to battery A short between them An open Refer to the following in Wiring Systems: Circuit Testing GMLAN Wiring Repairs Did you find and correct the condition? | Go to Step 18 | Go to Step 10 |
| 10 | Reconnect the IPM. Disconnect the farthest module from the DLC that is connected to high speed GMLAN serial data circuits. Refer to Data Link Connector (DLC) Schematics . Turn ON the ignition, with the engine OFF. Attempt to communicate with the IPM. Does the scan tool communicate with the IPM? | Go to Step 15 | Go to Step 11 |
| 11 | Turn OFF the ignition. Disconnect the farthest module from the DLC that is still connected to high speed GMLAN serial data circuits. Refer to Data Link Connector (DLC) Schematics . Turn ON the ignition, with the engine OFF. Attempt to communicate with the IPM. Does the scan tool communicate with the IPM? | Go to Step 12 | Go to Step 13 |
| 12 | Test the high speed GMLAN serial data circuits between the last 2 disconnected modules for: A short to ground A short to battery A short between them An open Refer to the following in Wiring Systems: Circuit Testing GMLAN Wiring Repairs Did you find and correct the condition? | Go to Step 18 | Go to Step 15 |
| 13 | Is the IPM the last module still connected to high speed GMLAN data circuits? | Go to Step 14 | Go to Step 11 |
| 14 | Turn OFF the ignition. Disconnect the IPM. Test the high speed GMLAN serial data circuits between IPM and the previous disconnected module for: A short to ground A short to battery A short between them An open Refer to the following in Wiring Systems: Circuit Testing GMLAN Wiring Repairs Did you find and correct the condition? | Go to Step 18 | Go to Step 16 |
| 15 | Test each of the high speed GMLAN circuits of the last disconnected module to the next module closer to DLC for an open. Refer to the following in Wiring Systems: Circuit Testing GMLAN Wiring Repairs Did you find and correct the condition? | Go to Step 18 | Go to Step 16 |
| 16 | Inspect for poor connections at the high speed GMLAN serial data circuits of the suspected module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 18 | Go to Step 17 |
| 17 | Replace the suspected module. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 18 | |
| 18 | Reconnect all of the disconnected modules. Install a scan tool. Turn ON the ignition, with the engine OFF. Select the Display DTCs function for each module. Record all of the displayed DTCs and the DTC status. Did you record any DTCs which begin with a "U" and with a current status? | Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information | Go to Step 19 |
| 19 | Did you record any DTCs which do not begin with a "U"? | Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information | Go to Step 20 |
| 20 | Did you diagnose all of the DTCs? | Go to Step 21 | Go to Step 18 |
| 21 | Use the scan tool in order to clear the DTCs. Did you complete the action? | System OK | |
| IMPORTANT |
|---|
| Make sure the CANdi module works fine. When functioning properly, CANdi's LED flashes. In the event of a problem, the LED will be constantly illuminated. |
| IMPORTANT |
|---|
| Turn ON the ignition, with the engine OFF, when testing for a short to voltage. Use the DMM MIN/MAX function to capture intermittent conditions. |
Scan Tool Does Not Communicate with High Speed GMLAN Device
The numbers below refer to the step numbers on the diagnostic table.
- 2: A current DTC U2100 71 or U2100 00 may be retrieved only from instrument panel module (IPM).
- 4: A partial malfunction in the low speed GMLAN serial data circuit uses a different procedure from a total malfunction of the low speed GMLAN serial data circuit. The scan tool communicates with the following modules on the low speed GMLAN serial data circuit: Audio amplifier Communication interface module (OnStar) Digital radio receiver (DRR) Driver door module (DDM) Driver door switch (DDS) Driver position module (DPM) Head up display (HUD) HVAC control module Inflatable restraint sensing and diagnostic module (SDM) Instrument panel cluster (IPC) Left rear door module (LRDM) Passenger door module (PDM) Radio Rear integration module (RIM) Remote control door lock receiver (RCDLR) Right rear door module (RRDM) Steering column lock control module (SCLCM) Television module
- 10: An open in the low speed GMLAN serial data circuit between the DLC and instrument panel module (IPM) will prevent the scan tool from communicating with any module on the low speed GMLAN bus. This condition will not set a DTC.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Data Link Connector (DLC) Schematics Connector End View Reference: Master Electrical Component List in Wiring Systems | |||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | IMPORTANT: Make sure the CANdi module works fine. When functioning properly, CANdi's LED flashes. In the event of a problem, the LED will be constantly illuminated. Refer to the Test Description for the list of modules that communicate with scan tool on low speed GMLAN bus.Did the scan tool communicate with any module on the low speed GMLAN serial data circuit? | Go to Step 5 | Go to Step 3 |
| 3 | Does the scan tool communicate with instrument panel module (IPM)? | Go to Step 4 | Go to Scan Tool Does Not Communicate with High Speed GMLAN Device |
| 4 | Did you retrieve DTC U2100 71 and/or U2100 00 set as current? | Go to DTC U2100 | Go to Step 7 |
| 5 | Did you record any DTCs in the range of U2100 to U2199? | Go to DTC U2105-U2199 | Go to Step 6 |
| 6 | Diagnose the non-communicating module by using the DTC U2100-U2199 procedure for the module which is not communicating. Refer to DTC U2105-U2199 . Did you complete the action? | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | |
| 7 | Turn OFF the ignition. Disconnect the scan tool from the data link connector (DLC). Inspect for poor connections at the DLC terminals 1 and 5. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | Go to Step 8 |
| 8 | Test the DLC ground circuit at terminal 5 for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | Go to Step 9 |
| 9 | Disconnect the instrument panel module (IPM). Inspect for poor connections at the low speed GMLAN serial data circuits of the IPM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | Go to Step 10 |
| 10 | Repair the low speed GMLAN serial data circuit between the DLC and the IPM for an open. Refer to Circuit Testing and GMLAN Wiring Repairs in Wiring Systems. Did you complete the action? | System OK | |
| IMPORTANT |
|---|
| Make sure the CANdi module works fine. When functioning properly, CANdi's LED flashes. In the event of a problem, the LED will be constantly illuminated. |
Scan Tool Does Not Communicate with Low Speed GMLAN Device
General Information to Setup the Instrument Panel Module (IPM)
| IMPORTANT | The Air Bag indicator light may remain ON after the instrument panel module (IPM) is replaced and during the setup procedure for the IPM until the procedure is completed and the ignition key is cycled OFF and ON. |
Before performing any of the setup procedures ensure the following
- The scan tool has been updated with the latest software version.
- The battery is fully charged.
- All modules on the serial data line are connected.
The following procedures must be performed when a new IPM is installed
- Setup New IPM/RIM
- Program vehicle identification number (VIN)
- Brake Pedal Position (BPP) Sensor Calibration
General Information to Setup the Rear Integration Module (RIM)
| IMPORTANT | The Air Bag indicator light may remain ON after the instrument panel module (IPM) is replaced and during the setup procedure for the IPM until the procedure is completed and the ignition key is cycled OFF and ON. |
Before performing any of the setup procedures ensure the following
- The scan tool has been updated with the latest software version.
- The battery is fully charged.
- All modules on the serial data line are connected.
Body Control System Description and Operation
The body control system consists of the following 2 modules
- The instrument panel module (IPM)
- The rear integration module (RIM)
IPM Overview
The main features of the instrument panel module (IPM) are
- The IPM is the gateway between low speed and high speed GMLAN serial data circuits.
- The IPM is the power mode master.
- The IPM controls electrical power management.
- The IPM controls multiple functions.
Fail-safe Operation
The remote control door lock receiver (RCDLR) is the backup power mode master (BPMM). The both IPM and RCDLR receive signals from the ignition mode switch, representing the mode switch data, through 2 different circuits. The RCDLR can determine and transmit all the system power modes per the lists above. Since the operation of the vehicle systems depends on the power mode, there is a fail-safe plan in place if the power mode message is not received from the IPM or RCDLR. The fail-safe plan covers modules with discrete ignition signal inputs as well as those modules using exclusively serial data control of power mode. The ECM and TCM behave differently.
See also:
• Master Electrical Component List