Battery, Charging System and Starting System Buick Rendezvous I

Fastener Tightening Specifications

Fastener Tightening Specifications

Battery Usage

Battery Usage

Starter Motor Usage

Starter Motor Usage

Generator Usage

Generator Usage

Scheme 1

Scheme 2

Scheme 3

Scheme 4

Scheme 5

Engine Electrical Connector End Views

Generator Connector End (LA1) Connector Part Information 12186568 4-Way F Metri-Pack 150 Series (BLK) Pin Wire Color Circuit No. Function A - - Not Used B RED 225 Generator Turn On Signal C-D - - Not Used

Generator Connector End (LY7) Connector Part Information 15355066 4-Way F Metri-Pack 150 Series (BG) Pin Wire Color Circuit No. Function A - - Not Used B OG 225 Generator Turn On Signal C GY 23 Generator Field Duty Cycle Signal D - - Not Used

Diagnostic Starting Point - Engine Electrical

Begin the system diagnosis with the Diagnostic System Check - Engine Electrical . The Diagnostic System Check will provide the following information

1. The identification of the control modules which command the system
2. The ability of the control modules to communicate through the serial data circuit
3. The identification of any stored diagnostic trouble codes (DTCs) and their status

The use of the Diagnostic System Check will identify the correct procedure for diagnosing the system and where the procedure is located.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. 4: Lack of communication may be because of a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.
2. 5: The symptom list in Symptoms will determine the correct diagnostic procedure to use.
3. 6: The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will collect all the available information before you perform tests.

Diagnostic System Check - Engine Electrical

Scan Tool Output Controls

Scan Tool Output Controls

Scan Tool Data List

Body Control Module (BCM) Scan Tool Data List

Powertrain Control Module (PCM, 3.4L LA1) Scan Tool Data List

Engine Control Module (ECM 3.6L LY7) Scan Tool Data List

Diagnostic Trouble Code (DTC) List

Diagnostic Trouble Code (DTC) List

Circuit Description

The BCM monitors the battery positive voltage and battery negative circuit voltage to determine if it is between 9.0-15.0 volts and sends this information out as a class 2 message to the VTD.

Conditions for Running the DTC

This DTC shall run only if the BCM has power, ground and the ignition in not in START mode.

Conditions for Setting the DTC

This DTC shall be set as current when the voltage falls below 9.0 volts for 1.2 milliseconds.

Action Taken When the DTC Sets

A message shall be sent out on the class 2 lines to illuminate the charge indicator and security lamp.

Conditions for Clearing the MIL/DTC

In order to clear the DTC from a current status the voltage shall be greater than 9.54 volts for 1200 milliseconds.

The numbers below refer to the step numbers on the diagnostic table.

1. 3: Tests for the proper operation of the complete circuit.
2. 4: Tests for the proper operation of the signal input circuit.

DTC B1327

The BCM has an internal voltage sensor with a dedicated circuit that monitors the battery positive voltage circuit to determine if it is below 18 volts.

This DTC shall run only if no communication codes are set.

The ignition positive voltage level is greater than 18 volts for approximately 1/2 seconds or more.

The BCM sets a DTC and disables the following State of Health (SOH) DTCs

1. DTC U1096
2. DTC U1255
3. DTC U1300
4. DTC U1301

The BCM illuminates the charge lamp indicator.

Conditions for Clearing the DTC

1. The battery positive voltage level is less than 17.9 volts for approximately 1/2 seconds.
2. A history DTC clears after 100 malfunction free ignition cycles.
3. The BCM receives the clear code command from the scan tool.

Diagnostic Aids

This DTC may set when the vehicle is placed on a battery charger, on fast charge, for a long period of time.

DTC B1328

The PCM monitors the system voltage to make sure that the voltage stays within the proper range. Damage to components, and incorrect data input can occur when the voltage is out of range. The PCM monitors the system voltage over an extended length of time. If the PCM detects a system voltage outside an expected range for the calibrated length of time, DTC P0560 will set.

1. System voltage below 9.0 volts or above 16.0 volts.
2. Engine speed above 650 RPM.
3. Vehicle speed below 40 Km/h (25 mph).

The PCM detects a system voltage out of range for 30 seconds.

1. The PCM will not illuminate the Malfunction Indicator Lamp (MIL).
2. The PCM will command a message to be displayed.
3. The PCM will store conditions which were present when the DTC set as Fail Records data only.

1. The PCM will command the message OFF after one trip in which the diagnostic test has been run and passed.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using the scan tool Clear DTC Information function.

DTC P0560

The engine control module (ECM) checks the system voltage to make sure that the voltage stays within the proper range. Damage to components, and incorrect input can occur when the voltage is out of range. The ECM monitors the system voltage over an extended length of time. If the ECM detects an excessively low system voltage, DTC P0562 will set.

1. Engine speed above 1,500 RPM.
2. System voltage between 9.5-18 volts.

The ECM detects a system voltage below 10 volts for 5 seconds.

1. The ECM will command a message to be displayed.
2. The ECM will not illuminate the malfunction indicator lamp (MIL).
3. The ECM will store conditions which were present when the DTC set as Fail Records data only.

1. The ECM will command the message OFF after one trip in which the diagnostic test has been run and passed.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using the scan tool Clear DTC Information function.

DTC P0562

The engine control module (ECM) checks the system voltage to make sure that the voltage stays within the proper range. Damage to components, and incorrect input can occur when the voltage is out of range. The ECM monitors the system voltage over an extended length of time. If the ECM detects an excessively high system voltage, DTC P0563 will set.

1. Engine speed above 1,500 RPM.
2. System voltage between 9.5-18 volts.

The ECM detects a system voltage above 16 volts for less than 1 second.

1. The ECM will command a message to be displayed.
2. The ECM will not illuminate the malfunction indicator lamp (MIL).
3. The ECM will store conditions which were present when the DTC set as Fail Records data only.

1. The ECM will command the message OFF after one trip in which the diagnostic test has been run and passed.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using the scan tool Clear DTC Information function.

DTC P0563

The engine control module (ECM) supplies a ground path for the STARTER relay when start enable has been requested. The ECM monitors this circuit for conditions that are incorrect for the commanded state. If the ECM detects an improper circuit condition, STARTER relay DTC P0615 will set.

System voltage is between 9 and 16 volts.

1. The ECM detects an improper voltage level on the output circuit that controls the STARTER relay.
2. The condition exists for at least 2 seconds.

1. The ECM will not illuminate the malfunction indicator lamp (MIL).
2. The ECM will store the conditions present when the DTC set as Fail Records data only.

1. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
2. The DTC can be cleared by using the scan tool Clear DTC Information function.

Ignition system DTCs set with the ignition switch in the Crank position if the STARTER relay or the starter is inoperative. When the ECM enables starter operation, the ECM also initiates the diagnostic test routines for DTCs P0335, P0340, and P0385. If a condition exists which prevents the engine from cranking, the ECM will not receive signal input from the CKP and CMP sensors, and the DTCs will set.

Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may assist in diagnosing the condition. The information may help determine how often the condition that set the DTC occurs.

The numbers below refer to the step numbers on the diagnostic table.

1. 2: Listen for an audible click when the STARTER relay operates. Press the ignition switch back and forth from the ON to Crank positions. Repeat this as necessary.
2. 3: Tests for voltage at the coil side of the STARTERrelay. The ECM IGN fuse supplies power to the coil side of the Crank relay.
3. 4: Verifies that the ECM is providing ground to the STARTER relay.
4. 5: Tests if ground is constantly being applied to the STARTER relay.

DTC P0615

The engine control module (ECM) supplies a ground path for the STARTER relay when start enable has been requested. The ECM monitors this circuit for conditions that are incorrect for the commanded state. If the ECM detects an improper circuit condition, starter relay DTC P0616 will set.

1. System voltage is between 8-16 volts.
2. The engine is running.

1. The ECM detects an improper voltage level on the output circuit that controls the STARTER relay.
2. The condition exists for at least 2 seconds.

1. The ECM will not illuminate the malfunction indicator lamp (MIL).
2. The ECM will store the conditions present when the DTC set as Fail Records data only.

1. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
2. The DTC can be cleared by using the scan tool Clear DTC Information function.

DTC P0616

The engine control module (ECM) supplies a ground path for the starter relay when start enable has been requested. The ECM monitors this circuit for conditions that are incorrect for the commanded state. If the ECM detects an improper circuit condition, starter relay DTC P0617 will set.

1. System voltage is between 8-16 volts.
2. The engine is running.

1. The ECM detects an improper voltage level on the output circuit that controls the starter relay.
2. The condition exists for at least 2 seconds.

1. The ECM will not illuminate the malfunction indicator lamp (MIL).
2. The ECM will store the conditions present when the DTC set as Fail Records data only.

1. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
2. The DTC can be cleared by using the scan tool Clear DTC Information function.

DTC P0617

The powertrain control module (PCM) uses the generator turn on signal circuit to control the generator. A high side driver within the PCM allows the PCM to turn the generator ON and OFF. When Generator operation is desired, the PCM sends a 5 volt signal to the voltage regulator via the generator turn on signal circuit. This causes the voltage regulator to begin controlling the generator field circuit. Once the Generator is enabled by the PCM, the voltage regulator controls generator output independently of the PCM. Under certain operating conditions, the PCM can turn Off the generator by turning Off the 5 volt signal on the generator turn on signal circuit. The PCM has fault detection circuitry which monitors the state of the generator turn on signal circuit. If the fault detection circuit senses a voltage other than what is expected, this DTC will set. The voltage regulator also contains fault detection circuitry. If the regulator detects a problem, the regulator will ground the generator turn on signal circuit, pulling the voltage low. This also causes the PCM to set the DTC.

The engine is running.

1. The generator turn on signal circuit voltage is low while the PCM is commanding the generator on.
2. The above condition is present for more than 30 seconds.

OR

1. The engine RPM is less than 2500.
2. The above conditions are present for more than 30 seconds.

1. The PCM stores the DTC information into memory when the diagnostic runs and fails.
2. The malfunction indicator lamp (MIL) will not illuminate.
3. The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records.
4. The PCM sends a class 2 message to the IPC to illuminate the charge indicator.

1. A History DTC will clear after forty consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
2. The current DTC will clear when the diagnostic runs and does not fail.
3. Use a scan tool in order to clear the MIL diagnostic trouble code.

DTC P0620

The engine control module (ECM) uses the generator field duty cycle signal circuit to monitor the duty cycle of the generator and fault indication. The generator field duty cycle signal circuit connects to the high side of the field winding in the generator. A pulse width modulated (PWM) high side driver in the voltage regulator turns the field winding ON and OFF. The ECM uses the PWM signal input to determine the generator load on the engine. This allows the ECM to adjust the idle speed to compensate for high electrical loads.

The ECM monitors the state of the generator field duty cycle signal circuit. When the engine is running, the ECM should detect a duty cycle that varies up to 100 percent. The ECM monitors the PWM signal using a key ON test and a RUN test. During the tests, if the ECM detects an out of range PWM signal, a DTC will set. When the DTC sets, the ECM will send a class 2 serial data message to the IPC and DIC to illuminate the charge indicator or display a charging message.

1. No generator, CKP sensors, or CMP sensor DTCs are set.
2. The engine is less than 3,000 RPM.
3. The generator has not been commanded OFF by the ECM or scan tool.

The ECM detects a PWM signal less than 5 percent for at least 15 seconds.

1. The ECM will not illuminate the malfunction indicator lamp (MIL).
2. The ECM will store the conditions present when the DTC set as Fail Records data only.
3. The ECM will send a class 2 serial data message to the IPC and DIC to illuminate the charge indicator or display a charging message.

1. The conditions for setting DTC P0625 are not present.
2. The DTC can be cleared by using the scan tool Clear DTC Information function.

DTC P0625

The engine control module (ECM) uses the generator field duty cycle signal circuit to monitor the duty cycle of the generator and fault indication. The generator field duty cycle signal circuit connects to the high side of the field winding in the generator. A pulse width modulated (PWM) high side driver in the voltage regulator turns the field winding ON and OFF. The ECM uses the PWM signal input to determine the generator load on the engine. This allows the ECM to adjust the idle speed to compensate for high electrical loads.

The ECM monitors the state of the generator field duty cycle signal circuit. When the key in the ON position, with the engine OFF, the ECM should detect a duty cycle that is 0 percent.

The ECM monitors the PWM signal using a key ON test and a RUN test. During the tests, if the ECM detects an out of range PWM signal, a DTC will set.

1. No generator, CKP sensors, or CMP sensor DTCs are set.
2. The engine is not running.
3. The key is in the ON position.

The ECM detects a PWM signal greater than 5 percent for at least 15 seconds.

1. The ECM will not illuminate the malfunction indicator lamp (MIL).
2. The ECM will store the conditions present when the DTC set as Fail Records data only.
3. The ECM will send a class 2 serial data message to the IPC and DIC to illuminate the charge indicator or display a charging message.

1. The conditions for setting DTC P0626 are not present.
2. The DTC can be cleared by using the scan tool Clear DTC Information function.

DTC P0626

The engine control module (ECM) uses the generator turn-on signal circuit to control the voltage output of the generator. When a different voltage is desired, the ECM will change the pulse width modulation (PWM) signal to the voltage regulator via the generator turn-on signal circuit. This causes the voltage regulator to the voltage output of the generator. The ECM has fault detection circuitry which monitors the state of the generator turn-on signal circuit. If the fault detection circuit senses a voltage other than what is expected, this DTC will set. The voltage regulator also contains fault detection circuitry. If the regulator detects a problem, the regulator will ground the generator turn-on signal circuit, pulling the voltage low. This also causes the ECM to set the DTC.

Key ON Test

1. The key is in the ON position for 5 seconds.
2. The engine is OFF.

Engine Run Test

1. The engine is running.
2. The engine speed is less than 3,000 RPM.

Key ON Test

1. The ECM detects a high signal voltage on the generator turn on signal circuit for at least 5 seconds.
2. The engine must be started.

During the RUN test, the ECM detects a low signal voltage on the generator turn on signal circuit for at least 5 seconds.

1. The ECM sends a class 2 message to the instrument panel cluster (IPC) to illuminate the charge indicator and/or turn on a message.
2. The ECM will not illuminate the malfunction indicator lamp (MIL).
3. The ECM will store the conditions present when the DTC set as Fail Records data only.

1. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
2. The DTC can be cleared by using the scan tool Clear DTC Information function.

DTC P1668

Symptoms - Engine Electrical

1. Perform «Diagnostic System Check - Engine Electrical»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) before using the Symptom Tables in order to verify that all of the following are true: There are no DTCs set. The control modules can communicate via the serial data link.
2. Review the system descriptions and operations in order to familiarize yourself with the system functions. Refer to one of the following system operations: «Battery Description and Operation»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) «Starting System Description and Operation»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system__starting-system-description-and-operation) «Charging System Description and Operation»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system)

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the starting and charging systems. Refer to «Checking Aftermarket Accessories»(/buick/rendezvous/i-2001-2007/remont/body-electrical/#wiring-systems-diagnostic-information-and-procedures__checking-aftermarket-accessories) in Wiring Systems.
2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom

1. «Starter Solenoid Does Not Click»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system__starter-solenoid-does-not-click)
2. «Starter Solenoid Clicks, Engine Does Not Crank»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system)
3. «Engine Cranks Slowly»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system__engine-cranks-slowly)
4. «Charge Indicator Always On»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system__charge-indicator-always-on)
5. «Charge Indicator Inoperative»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system__charge-indicator-inoperative)
6. «Battery Inspection/Test»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system)
7. «Battery Electrical Drain/Parasitic Load Test»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system)
8. «Battery Common Causes of Failure»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system__battery-common-causes-of-failure)
9. «Starter Motor Noise Diagnosis»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system)
10. «Charging System Test»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system__charging-system-test)
11. «Generator Noise Diagnosis»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system)

Tools Required

J 42000 Battery Tester. See Special Tools and Equipment .

Follow these instructions in order to avoid an incorrect diagnosis because of connections

1. If testing the vehicle with the battery cables still connected, wiggle the J 42000 clips on the terminal bolt. See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) . This may cut through any coating or through any oxidation that may be present on the bolt. Even new bolts contain a protective coating that may insulate or cause a resistance in the test circuit.
2. If correct connections to the battery terminal bolts in the vehicle are in doubt, perform the following steps: Disconnect the negative battery cable. Disconnect the positive battery cable. Install the test adapters on the terminals. Follow the instructions for an Out-of-Vehicle test.
3. If the tester displays a REPLACE BATTERY or BAD CELL-REPLACE result for a battery tested in the vehicle with the battery cables connected, perform the following steps: Disconnect the negative battery cable. Disconnect the positive battery cable. Install the tester adapters. Follow the instructions for an Out-of-Vehicle test. Replace the battery only if the Out-of-Vehicle test shows a REPLACE BATTERY or BAD CELL-REPLACE result. This prevents battery replacements that are due only to faulty battery cable connections.
4. Use the correct terminal adapters. Do not use any common bolts or a combination of bolts, nuts, and or washers as adapters when testing the battery. Use the test adapters that are provided with the J 42000 or P/N 12303040 terminal adapters. See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) . If the adapters that are provided with the J 42000 require replacement, use P/N 12303040. See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) . Any other adapter may not contact the correct areas of the battery terminal, causing a resistance that may result in an invalid battery test result.

Battery Inspection/Test

J 42000 Battery Tester. See Special Tools and Equipment .

1. For best results, use an automatic taper-rate battery charger with a voltage capability of 16 volts.
2. The charging area should be well ventilated.
3. Do not charge a battery that appears to be frozen. Allow the battery to warm to room temperature and test it using the J 42000 before charging. See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .

Battery State of Charge

The maintenance-free batteries SOC is estimated by reading the voltage of the battery across the battery terminals. Because the voltage is affected by current flow into or out of the battery, the engine must be stopped and all electrical loads turned OFF, including parasitic loads, when checking the voltage. The voltage can also be affected if the battery has just been charged or discharged, so it is important to consider what has happened to the battery in the time just before testing. Use the following procedure to determine the batteries SOC

1. Be sure all electrical loads are turned OFF.
2. Determine whether the battery has been used in a vehicle or charged within the past 12 hours. If the answer is no, the terminal voltage will be stabilized and no action is necessary before reading the voltage. Skip to step 3. If the answer is yes, terminal voltage will not be stabilized and you should wait 12 hours since the last time the battery was used.
3. Estimate the battery temperature by determining the average temperature to which the battery has been exposed for the past 12 hours.
4. Measure the battery voltage at the battery terminals. Refer to the following table to determine the SOC according to the estimated battery temperature

Battery Charging

Use the SOC information as follows

1. A battery with a SOC that is below 65 percent must always be recharged before returning it to service or continuing storage.
2. A battery with a SOC that is 65 percent or greater is generally considered to be charged enough in order to be returned to normal service or in order to continue storage. However, if the battery is being used in slow traffic or with short drive times, or if the temperature is very hot or very cold, the battery should be fully charged, to at least 90 percent, before returning it to service or continuing storage.

Charging Time Required

The time required to charge a battery will vary depending upon the following factors

1. The battery charger capacity-The higher the charger amperage, the less time it will take to charge the battery.
2. The SOC of the battery-A completely discharged battery requires more than twice as much charging time as a half charged battery. In a discharged battery with a voltage below 11 volts, the battery has a very high internal resistance and may only accept a very low current at first. Later, as the charging current causes the acid content to increase in the electrolyte, the charging current will increase. Extremely discharged batteries may not activate the reversed voltage protection in some chargers. Refer to the manufacturer's instructions for operating this circuitry.
3. The temperature of the battery-The colder the battery is, the more time it takes to recharge the battery. The charging current accepted by a cold battery is very low at first. As the battery warms, the charging current will increase.

Charging Procedure

Note. Turn OFF the ignition when connecting or disconnecting the battery cables, the battery charger or the jumper cables. Failure to do so may damage the PCM or other electronic components.

Note. Refer to Fastener Notice in Cautions and Notices.

When charging side-terminal batteries with the battery cables connected, connect the charger to the positive cable bolt and to a ground located away from the battery. When charging side-terminal batteries with the battery cables disconnected, install the battery side terminal adapters and connect the charger to the adapters.

Tighten: Tighten the battery side terminal adapters to 15 N.m (11 lb ft).

Use the following procedure to charge the battery

1. Turn OFF the charger.
2. Ensure that all of the battery terminal connections are clean and tight.
3. Connect the charger positive lead to the battery positive terminal on the battery or the remote jumper stud underhood.
4. Connect the negative charger lead to a solid engine ground or to a ground stud in the engine compartment that is connected directly to the battery negative terminal, but away from the battery. If the negative battery cable is disconnected and a terminal adapter is being used, connect directly to the adapter.
5. Turn ON the charger and set to the highest setting for normal charging.
6. Inspect the battery every half hour after starting the battery charger. Charge the battery until the taper-rate charger indicates that the battery is fully charged. Estimate the battery temperature by feeling the side of the battery. If it feels hot to the touch or its temperature is over 45°C (125°F), discontinue charging and allow the battery to cool before resuming charging.
7. After charging, test the battery. Refer to «Battery Inspection/Test»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .

J 38758 Parasitic Draw Test Switch. See Special Tools and Equipment .

1. Be sure to rule out any possible obvious influences, such as customer error or aftermarket equipment.
2. Customer driving habits, such as regular short trips. This does not allow enough time to properly charge the battery. Refer to «Battery Description and Operation»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
3. Verify that the battery and charging system are in proper working order. Refer to «Battery Charging»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) and «Charging System Test»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system__charging-system-test) .
4. A battery discharging for no apparent reason while the vehicle is parked can be caused by an intermittent draw, such as a module waking up, or a continuous draw, such as a dome light or stuck relay.
5. Some systems and modules such as OnStar®, and regulated voltage control (RVC), if equipped, are designed to wake-up, perform a task, and go back asleep at regular intervals. Refer to «Body Control System Description and Operation»(/buick/rendezvous/i-2001-2007/remont/communication-devices/#body-control-system) in Body Control System for the system or modules description and operation.
6. Remote keyless entry (RKE) will wake up due to an outside input. Refer to «Keyless Entry System Description and Operation»(/buick/rendezvous/i-2001-2007/remont/door-locks-anti-theft-systems/#keyless-entry-system) in Keyless Entry.
7. The battery run down time will vary depending on cold cranking amperage (CCA) and reserve capacity (RC). If the CCA and RC are higher, then the battery run down time would be longer. If the CCA and RC are lower, then the battery run down time would be shorter. The graph below indicates roughly how many days a 690 CCA battery with at 110 min. RC (60.5 AH) starting at 80 percent state of charge will last with a constant current draw until it reaches 50 percent state of charge. Differences in battery rating and temperature will affect the results.

Battery Electrical Drain/Parasitic Load Test

Note. Do not turn the parasitic draw test switch to the OFF position with the engine running. Damage will occur to the vehicle's electrical system.

Note. The test switch must be in the ON position when removing the fuses in order to maintain continuity in the electrical system. This avoids damaging the digital multimeter due to accidental overloading, such as a door being opened to change a fuse.

1. Disconnect the battery negative cable from the battery negative terminal.
2. Install the male end of the J 38758 to the battery ground terminal. See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
3. Turn the J 38758 knob to the OFF position. See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
4. Install the battery negative cable to the female end of the J 38758 . See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
5. Connect a 10A fused jumper wire to the test switch tool terminals.
6. Turn the J 38758 knob to the ON position. See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
7. Road test the vehicle and activate ALL of the accessories, including the radio and air conditioning. This may take up to 30 minutes.
8. Park the vehicle. Turn the ignition switch to the OFF position and remove the ignition switch key.
9. Turn the J 38758 knob to the OFF position. See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) . The current now flows through the jumper wire.
10. Wait 1 minute. If the fuse blows, install an inductive ammeter and go to step 20.
11. Remove the fused jumper wire.
12. Set a digital multimeter to the 10A scale.
13. Connect the digital multimeter to the test switch tool terminals.
14. Turn the J 38758 knob to the OFF position. See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) . The current flows now through the digital multimeter.
15. Wait 1 minute. Check and record the current reading. When there is a current reading on 2A or less, turn the J 38758 knob to the ON position. See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) . The electrical current will now pass through the switch. Then switch the digital multimeter down to the 2A scale for a more accurate reading when the J 38758 knob is turned OFF. See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
16. Turn the J 38758 knob to the OFF position. See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) . Wait 15 minutes for most vehicles.
17. Check and record the current reading.
18. Note the battery reserve capacity, amp hour rating. Refer to «Battery Usage»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system__battery-usage) . Divide the reserve capacity by 4, amp hour rating by 2.4. Compare this to the multimeter milliampere reading taken in the previous step. The parasitic current drain should not exceed this number. Example: If a battery has a reserve capacity of 100 minutes, (60 A/H) the current drain should not exceed 25 mA.
19. If excessive current drain is not found at this time and there are no other apparent causes, complete the following
20. Using the MIN/MAX function of the digital multimeter, monitor the parasitic drain overnight or during the day. This will determine if something has been activated during that time frame.
21. When the vehicle has an unacceptable amount of parasitic current drain, remove each fuse one at a time until the current drain falls to an acceptable level. This will indicate which circuit is causing the drain. Refer to «Power Distribution Schematics»(/buick/rendezvous/i-2001-2007/remont/body-electrical/#wiring-systems-diagnostic-information-and-procedures) in Wiring Systems to diagnose exactly which part of the suspect circuit is causing the parasitic drain. In some cases a non-fused circuit or component, such as a relay, is the cause of excessive parasitic current drain.
22. Repeat the parasitic current drain test procedure after any repair has been completed to make sure that the parasitic current drain is at an acceptable level.
23. When the cause of the excessive current drain has been located and repaired, remove the J 38758 . See «Special Tools and Equipment»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
24. Connect the battery negative cable to the battery negative terminal.

Battery Common Causes of Failure

A battery is not designed to last forever. With proper care, however, the battery will provide years of good service. If the battery tests good but still fails to perform well, the following are some of the more common causes

1. A vehicle accessory was left on overnight.
2. The driving speeds have been slow with frequent stops, stop-and-go driving, with many electrical accessories in use, particularly air conditioning, headlights, wipers, heated rear window, cellular telephone, etc.
3. The electrical load has exceeded the generator output, particularly with the addition of aftermarket equipment.
4. Existing conditions in the charging system, including the following possibilities: A slipping belt A bad generator
5. The battery has not been properly maintained, including a loose battery hold down or missing battery insulator if used.
6. There are mechanical conditions in the electrical system, such as a short or a pinched wire, attributing to power failure. Refer to «General Electrical Diagnosis Procedures»(/buick/rendezvous/i-2001-2007/remont/body-electrical/#wiring-systems-diagnostic-information-and-procedures) in Wiring Systems.

Electrolyte Freezing

The freezing point of electrolyte depends on its specific gravity. A fully charged battery will not freeze until the ambient temperature gets below -54°C (-65°F). However, a battery with a low state of charge may freeze at temperatures as high as -7°C (20°F). Since freezing may ruin a battery, the battery should be protected against freezing by keeping it properly charged. As long as the green eye is visible in the hydrometer, the freezing point of the battery will be somewhere below -32°C (-25°F).

Battery Protection During Vehicle Storage

Certain devices on the vehicle maintain a small continuous current drain, parasitic load, on the battery. A battery that is not used for an extended period of time will discharge. Eventually permanent damage will result. Discharged batteries will also freeze in cold weather. Refer to Battery Inspection/Test .

In order to maintain the battery state of charge while storing the vehicle for more than 30 days

1. Ensure that the green dot is visible in the built-in hydrometer.
2. Disconnect the battery ground cable to protect the battery from discharge by parasitic current drains.

When the battery cannot be disconnected

1. Maintain a high state of charge.
2. Establish a regular schedule for recharging the battery every 20-45 days.

A battery that has remained in a discharged state for a long period of time is difficult to recharge or may be permanently damaged.

Jump Starting in Case of Emergency

Note. This vehicle has a 12 volt, negative ground electrical system. Make sure the vehicle or equipment being used to jump start the engine is also 12 volt, negative ground. Use of any other type of system will damage the vehicle's electrical components.

1. Position the vehicle with the booster battery so that the jumper cables will reach. Do not let the 2 vehicles touch. Make sure that the jumper cables do not have loose ends, or missing insulation.
2. Place an automatic transmission in PARK. If equipped with a manual transmission, place in NEUTRAL and block the wheels.
3. Turn OFF all electrical loads on both vehicles that are not needed.
4. Turn OFF the ignition on both vehicles.
5. Connect the red positive (+) cable to the battery positive (+) terminal (2) of the vehicle with the discharged battery. Use a remote positive (+) terminal if the vehicle has one.
6. Connect the red positive (+) cable to the positive (+) terminal (1) of the booster battery. Use a remote positive (+) terminal if the vehicle has one.
7. Connect the black negative (-) cable to the negative (-) terminal (3) of the booster battery.
8. The final connection is made to a heavy, unpainted metal engine part (4) of the vehicle with the discharged battery. This final attachment must be at least 46 cm (18 in) away from the dead battery.
9. Start the engine of the vehicle that is providing the boost.
10. Crank the engine of the vehicle with the discharged battery.
11. The black negative (-) cable must be first disconnected from the vehicle that was boosted (4).
12. Disconnect the black negative (-) cable from the negative (-) terminal (3) of the booster battery.
13. Disconnect the red positive (+) cable from the positive (+) terminal (1) of the booster battery.
14. Disconnect the red positive (+) cable from the remote positive (+) terminal (2) of the vehicle with the discharged battery.

Charging System Test

Charging System Test

Charge Indicator Always On

Charge Indicator Always On

Charge Indicator Inoperative

Charge Indicator Inoperative

Noise from a generator may be due to electrical or mechanical noise. Electrical noise, magnetic whine, usually varies with the electrical load placed on the generator and is a normal operating characteristic of all generators. When diagnosing a noisy generator, it is important to remember that loose or misaligned components around the generator may transmit the noise into the passenger compartment and that replacing the generator may not solve the problem.

Generator Noise Diagnosis

Starter Solenoid Does Not Click

Starter Solenoid Does Not Click

The steps below refer to the test steps in the diagnostic table.

1. 3: Inspect the engine for mechanical failure, or the binding of driven components including driveline related components.

Starter Solenoid Clicks, Engine Does Not Crank

Engine Cranks Slowly

Inspect the following items

1. Battery - Perform the Battery Inspection/Test. Refer to «Battery Inspection/Test»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
2. Wiring - Inspect the wiring for damage. Inspect all connections to the starter motor, the solenoid, the battery, and all ground connections. Refer to «Circuit Testing»(/buick/rendezvous/i-2001-2007/remont/body-electrical/#wiring-systems-diagnostic-information-and-procedures__circuit-testing) , «Wiring Repairs»(/buick/rendezvous/i-2001-2007/remont/body-electrical/#wiring-systems-diagnostic-information-and-procedures__wiring-repairs) , «Testing for Intermittent Conditions and Poor Connections»(/buick/rendezvous/i-2001-2007/remont/body-electrical/#wiring-systems-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor) , and «Connector Repairs»(/buick/rendezvous/i-2001-2007/remont/body-electrical/#wiring-systems-diagnostic-information-and-procedures__connector-repairs) in Wiring Systems.
3. Engine - Verify that the engine is not seized.

If the battery, the wiring, and the engine are functioning properly, and the engine continues to crank slowly, replace the starter motor. Refer to Starter Motor Replacement (LA1) or Starter Motor Replacement (LY7) .

1. Inspect the flywheel ring gear for damage or unusual wear.
2. Shim the starter as required.
3. In order to add pinion to ring gear clearance a full size shim must be used. Do not shim only one starter mounting bolt. There are three shims available in different shapes, for clearance, all are 1 mm (0.039 in.) thick.

Starter Motor Noise Diagnosis

Removal Procedure

1. Record all of the customer's radio station presets.
2. Turn off all the lamps and accessories.
3. Turn the ignition OFF.
4. Remove the battery ground (negative) cable and bolt from the battery.

Installation Procedure

1. Install the battery ground (negative) cable and bolt to the battery. Tighten: Tighten the battery terminal bolt to 16 N.m (12 lb ft).
2. Program all of the customer's radio station presets and set the radio clock to the current time.

1. Record all of the customer's radio station presets.
2. Turn off all the lamps and accessories.
3. Turn the ignition OFF.
4. Loosen the battery ground (negative) cable terminal nut.
5. Remove the battery negative cable from the battery.

1. Install the battery ground (negative) cable to the battery. Tighten: Tighten the battery terminal nut to 9 N.m (80 lb in).
2. Program all of the customer's radio station presets and set the radio clock to the current time.

1. Remove the battery ground (negative) cable from the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
2. Remove the battery ground (negative) cable bolt from the core support.
3. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/rendezvous/i-2001-2007/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
4. Remove the lower radiator baffle. Refer to «Radiator Air Baffle Assemblies and Deflectors»(/buick/rendezvous/i-2001-2007/remont/cooling-fan/#engine-cooling-system) in Engine Cooling.
5. Remove the battery cable conduit from the conduit retainers.
6. Remove the battery cable from the conduit.
7. Remove the battery ground (negative) cable nut and cable from the transaxle stud.
8. Lower the vehicle.
9. Remove the battery ground (negative) cable from the vehicle.

1. Install the battery ground (negative) cable to the vehicle.
2. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/rendezvous/i-2001-2007/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
3. Install the battery ground (negative) cable and nut to the transaxle stud. Tighten: Tighten the nut to 25 N.m (18 lb ft).
4. Install the battery cable to the conduit.
5. Install the battery cable conduit to the conduit retainers.
6. Install the lower radiator baffle. Refer to «Radiator Air Baffle Assemblies and Deflectors»(/buick/rendezvous/i-2001-2007/remont/cooling-fan/#engine-cooling-system) in Engine Cooling.
7. Lower the vehicle.
8. Install the battery ground (negative) cable and bolt to the inner fender. Tighten: Tighten the bolt to 5 N.m (44 lb in).
9. Install the battery ground (negative) cable to the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .

1. Remove the battery ground (negative) cable from the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
2. Remove the battery ground (negative) cable bolt from the core support.
3. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/rendezvous/i-2001-2007/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
4. Remove the lower radiator baffle. Refer to «Radiator Air Baffle Assemblies and Deflectors»(/buick/rendezvous/i-2001-2007/remont/cooling-fan/#engine-cooling-system) in Engine Cooling.
5. Remove the battery cable conduit from the conduit retainers.
6. Remove the battery cable from the conduit.
7. Remove the battery ground (negative) cable bolt and cable from the engine block.
8. Lower the vehicle.
9. Remove the battery ground (negative) cable from the vehicle.

1. Install the battery ground (negative) cable to the vehicle.
2. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/rendezvous/i-2001-2007/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
3. Install the battery ground (negative) cable and bolt to the engine block. Tighten: Tighten the nut to 25 N.m (18 lb ft).
4. Install the battery cable to the conduit.
5. Install the battery cable conduit to the conduit retainers.
6. Install the lower radiator baffle. Refer to «Radiator Air Baffle Assemblies and Deflectors»(/buick/rendezvous/i-2001-2007/remont/cooling-fan/#engine-cooling-system) in Engine Cooling.
7. Lower the vehicle.
8. Install the battery ground (negative) cable and bolt to the core support. Tighten: Tighten the battery ground (negative) cable at core support bolt to 5 N.m (44 lb in).
9. Install the battery ground (negative) cable to the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .

When replacing battery cables, be sure to use replacement cables that are the same type, gauge and length.

1. Remove the battery ground (negative) cable from the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
2. Remove the battery positive cable from the battery.
3. Remove the battery positive cable nut and cable from the underhood electrical center.
4. Remove the battery positive cable nut and cable from the generator.
5. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/rendezvous/i-2001-2007/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
6. Remove the lower radiator baffle. Refer to «Radiator Air Baffle Assemblies and Deflectors»(/buick/rendezvous/i-2001-2007/remont/cooling-fan/#engine-cooling-system) in Engine Cooling.
7. Remove the battery cable conduit from the conduit retainers.
8. Remove the starter motor BAT terminal nut from the starter motor.
9. Remove the battery positive cable from the starter motor BAT terminal.
10. Lower the vehicle.
11. Remove the battery positive cable from the vehicle.

1. Install the battery positive cable to the vehicle.
2. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/rendezvous/i-2001-2007/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
3. Install the battery positive cable and nut to the starter motor BAT terminal. Tighten: Tighten the nut to 10 N.m (89 lb in).
4. Install the battery positive cable to the conduit.
5. Install the battery cable conduit to the conduit retainers.
6. Install the lower radiator baffle. Refer to «Radiator Air Baffle Assemblies and Deflectors»(/buick/rendezvous/i-2001-2007/remont/cooling-fan/#engine-cooling-system) in Engine Cooling.
7. Lower the vehicle.
8. Connect the battery positive cable to the generator. Refer to «Generator Replacement (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Generator Replacement (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
9. Install the battery positive cable and nut to the underhood electrical center. Tighten: Tighten the nut to 10 N.m (89 lb in).
10. Install the battery positive cable and bolt to the battery. Tighten: Tighten the bolt to 16 N.m (12 lb ft).
11. Install the battery ground (negative) cable to the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .

When replacing battery cables, be sure to use replacement cables that are the same type, gage and length.

1. Remove the battery ground (negative) cable from the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
2. Loosen the battery terminal nut.
3. Remove the battery positive cable from the battery.
4. Remove the battery positive cable nut and cable from the underhood electrical center.
5. Remove the battery positive cable nut and cable from the generator.
6. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/rendezvous/i-2001-2007/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
7. Remove the lower radiator baffle. Refer to «Radiator Air Baffle Assemblies and Deflectors»(/buick/rendezvous/i-2001-2007/remont/cooling-fan/#engine-cooling-system) in Engine Cooling.
8. Remove the battery cable conduit from the conduit retainers.
9. Remove the starter motor BAT terminal nut from the starter motor.
10. Remove the battery positive cable from the starter motor BAT terminal.
11. Lower the vehicle.
12. Remove the battery positive cable from the vehicle.

1. Install the battery positive cable to the vehicle.
2. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/rendezvous/i-2001-2007/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
3. Install the battery positive cable and nut to the starter motor BAT terminal. Tighten: Tighten the starter motor BAT terminal nut to 13 N.m (115 lb in).
4. Install the battery positive cable to the conduit.
5. Install the battery cable conduit to the conduit retainers.
6. Install the lower radiator baffle. Refer to «Radiator Air Baffle Assemblies and Deflectors»(/buick/rendezvous/i-2001-2007/remont/cooling-fan/#engine-cooling-system) in Engine Cooling.
7. Lower the vehicle.
8. Connect the battery positive cable to the generator. Refer to «Generator Replacement (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Generator Replacement (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
9. Install the battery positive cable and nut to the underhood electrical center. Tighten: Tighten the nut to 10 N.m (89 lb in).
10. Install the battery positive cable to the battery. Tighten: Tighten the battery terminal nut to 9 N.m (80 lb in).
11. Install the battery ground (negative) cable to the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .

Battery Replacement

1. Remove and reposition the underhood electrical center. Refer to «Underhood Electrical Center or Junction Block Replacement»(/buick/rendezvous/i-2001-2007/remont/body-electrical/#wiring-systems-diagnostic-information-and-procedures) in Wiring Systems.
2. Remove the front end sheet metal diagonal brace. Refer to «Brace Replacement - Front Fender Upper Diagonal - Right»(/buick/rendezvous/i-2001-2007/remont/exterior-body-panels/#body-front-end) in Body Front End.
3. Remove the battery ground (negative) cable from the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
4. Remove the battery positive cable from the battery.
5. Remove the battery hold down retainer.
6. Remove the battery.
7. Remove the battery insulator from the battery.

1. Install the battery insulator to the battery.
2. Install the battery and ensure that the battery is positioned properly in the battery tray.
3. Install the battery hold down retainer.
4. Install the battery hold down retainer bolt. Tighten: Tighten the bolt to 17 N.m (13 lb ft).
5. Install the battery positive cable and bolt to the battery. Tighten: Tighten the bolt to 16 N.m (12 lb ft).
6. Install the battery ground (negative) cable to the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
7. Install the front end sheet metal diagonal brace. Refer to «Brace Replacement - Front Fender Upper Diagonal - Right»(/buick/rendezvous/i-2001-2007/remont/exterior-body-panels/#body-front-end) in Body Front End.
8. Install the underhood electrical center. Refer to «Underhood Electrical Center or Junction Block Replacement»(/buick/rendezvous/i-2001-2007/remont/body-electrical/#wiring-systems-diagnostic-information-and-procedures) in Wiring Systems.

1. Remove the battery. Refer to «Battery Replacement»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system__battery-replacement) .
2. Remove the battery tray bolts.
3. Remove the battery tray.

1. Install the battery tray.
2. Install the battery tray bolts. Tighten: Tighten the battery tray bolts to 10 N.m (89 lb in).
3. Install the battery. Refer to «Battery Replacement»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system__battery-replacement) .

1. Disconnect the battery ground (negative) cable from the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
2. Raise and suitably support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/rendezvous/i-2001-2007/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
3. Remove radiator air baffle assembly. Refer to «Radiator Air Baffle Assemblies and Deflectors»(/buick/rendezvous/i-2001-2007/remont/cooling-fan/#engine-cooling-system) in Engine Cooling.
4. Remove the starter motor BAT terminal nut and electrical leads.
5. Remove the starter motor S terminal nut and electrical lead.
6. Remove the torque converter cover. Refer to «Torque Converter Cover Replacement (LA1)»(/buick/rendezvous/i-2001-2007/remont/automatic-trans/#automatic-transaxle-4t65-e-introduction-service-replacement) or «Torque Converter Cover Replacement (LY7)»(/buick/rendezvous/i-2001-2007/remont/automatic-trans/#automatic-transaxle-4t65-e-introduction-service-replacement) in Automatic Transaxle - 4T65-E.
7. Remove the starter motor bolts.
8. Remove the starter motor.

1. Install the starter motor.
2. Install the starter motor bolts. Tighten: Tighten the starter motor bolts to 47 N.m (35 lb ft).
3. Install the torque converter cover. Refer to «Torque Converter Cover Replacement (LA1)»(/buick/rendezvous/i-2001-2007/remont/automatic-trans/#automatic-transaxle-4t65-e-introduction-service-replacement) or «Torque Converter Cover Replacement (LY7)»(/buick/rendezvous/i-2001-2007/remont/automatic-trans/#automatic-transaxle-4t65-e-introduction-service-replacement) in Automatic Transaxle - 4T65-E.
4. Install the starter motor S terminal electrical lead and nut. Tighten: Tighten the starter motor solenoid S terminal nut to 3 N.m (27 lb in).
5. Install the starter motor BAT terminal electrical leads and nut. Tighten: Tighten the starter motor solenoid BAT terminal nut to 10 N.m (89 lb in).
6. Install radiator air baffle assembly. Refer to «Radiator Air Baffle Assemblies and Deflectors»(/buick/rendezvous/i-2001-2007/remont/cooling-fan/#engine-cooling-system) in Engine Cooling.
7. Lower the vehicle.
8. Install the battery ground (negative) cable to the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .

1. Disconnect the battery ground (negative) cable from the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
2. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/rendezvous/i-2001-2007/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
3. Remove the radiator air baffle. Refer to «Radiator Air Baffle Assemblies and Deflectors»(/buick/rendezvous/i-2001-2007/remont/cooling-fan/#engine-cooling-system) in Engine Cooling.
4. Remove the starter motor BAT terminal nut and electrical leads.
5. Remove the starter motor bolts.
6. Remove the starter motor.

1. Install the starter motor.
2. Install the starter motor bolts. Tighten: Tighten the starter motor bolts to 50 N.m (37 lb ft).
3. Install the starter motor S terminal electrical connector.
4. Install the battery positive cable and the BAT terminal nut to the starter motor BAT terminal. Tighten: Tighten the starter motor BAT terminal nut to 13 N.m (115 lb in).
5. Install radiator air baffle assembly. Refer to «Radiator Air Baffle Assemblies and Deflectors»(/buick/rendezvous/i-2001-2007/remont/cooling-fan/#engine-cooling-system) in Engine Cooling.
6. Lower the vehicle.
7. Install the battery ground (negative) cable to the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .

1. Remove the generator. Refer to «Generator Replacement (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Generator Replacement (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
2. Remove the drive belt tensioner. Refer to «Drive Belt Tensioner Replacement»(/buick/rendezvous/i-2001-2007/remont/mechanical/#engine-mechanical-34l-la1) in Engine Mechanical-3.4L.
3. Remove the generator bracket bolts.
4. Remove the generator bracket.

1. Install the generator bracket.
2. Install the generator bracket bolts. Tighten: Tighten the generator bracket bolts in the sequence shown to 50 N.m (37 lb ft).
3. Install the drive belt tensioner. Refer to «Drive Belt Tensioner Replacement»(/buick/rendezvous/i-2001-2007/remont/mechanical/#engine-mechanical-34l-la1) in Engine Mechanical-3.4L.
4. Install the generator. Refer to «Generator Replacement (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Generator Replacement (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .

1. Remove the battery ground (negative) cable from the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
2. Rotate and secure the engine forward to access rear generator bolts. Refer to «Rotating the Engine for Service Access»(/buick/rendezvous/i-2001-2007/remont/mechanical/#engine-mechanical-34l-la1) in Engine Mechanical - 3.4L.
3. Remove the generator B+ terminal nut.
4. Remove the generator B+ lead.
5. Remove the generator electrical connector.
6. Remove the drive belt from the generator. Refer to «Drive Belt Replacement»(/buick/rendezvous/i-2001-2007/remont/mechanical/#engine-mechanical-34l-la1) in Engine Mechanical - 3.4L.
7. Remove the generator front bolt.
8. Remove the generator rear bolts.
9. Remove the generator from the generator bracket and position the generator above the drive axle.
10. Remove the drive belt tensioner. Refer to «Drive Belt Tensioner Replacement»(/buick/rendezvous/i-2001-2007/remont/mechanical/#engine-mechanical-34l-la1) in Engine Mechanical-3.4L.
11. Remove the generator bracket. Refer to «Generator Bracket Replacement»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
12. Remove the power steering pipes from the power steering pipe retainer.
13. Remove the fuel pressure test port (schrader valve) cap from the fuel injector rail.
14. Remove the power steering pump and reposition the power steering pump in front of the timing chain cover in order to provide access for the generator. Refer to «Power Steering Pump Replacement (LA1 )»(/buick/rendezvous/i-2001-2007/remont/manual-power-steering/#power-steering-system) or «Power Steering Pump Replacement (LY7)»(/buick/rendezvous/i-2001-2007/remont/manual-power-steering/#power-steering-system) in Power Steering System.
15. Remove electrical harness from retainer on right fender well and position aside.
16. Remove the generator from the vehicle.

1. Install the generator to the vehicle and position the generator above the drive axle.
2. Install electrical harness to retainer on right fender well.
3. Install the power steering pump to the engine. Refer to «Power Steering Pump Replacement (LA1 )»(/buick/rendezvous/i-2001-2007/remont/manual-power-steering/#power-steering-system) or «Power Steering Pump Replacement (LY7)»(/buick/rendezvous/i-2001-2007/remont/manual-power-steering/#power-steering-system) in Power Steering System.
4. Install the fuel pressure test port (schrader valve) cap to the fuel injector rail.
5. Install the power steering pipes from the power steering pipe retainer.
6. Install the generator bracket. Refer to «Generator Bracket Replacement»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
7. Install the drive belt tensioner. Refer to «Drive Belt Tensioner Replacement»(/buick/rendezvous/i-2001-2007/remont/mechanical/#engine-mechanical-34l-la1) in Engine Mechanical - 3.4L.
8. Install the generator to the generator bracket and position the generator above the drive axle.
9. Install the drive belt tensioner. Refer to «Drive Belt Tensioner Replacement»(/buick/rendezvous/i-2001-2007/remont/mechanical/#engine-mechanical-34l-la1) in Engine Mechanical - 3.4L.
10. Install the generator to the generator bracket.
11. Install the generator front bolt.
12. Install the generator rear bolts. Tighten: Tighten the generator bolts to 50 N.m (37 lb ft).
13. Install the drive belt. Refer to «Drive Belt Replacement»(/buick/rendezvous/i-2001-2007/remont/mechanical/#engine-mechanical-34l-la1) in Engine Mechanical - 3.4L.
14. Install the generator electrical connector.
15. Install the generator B+ lead.
16. Install the generator B+ terminal nut. Tighten: Tighten the generator B+ terminal nut to 13 N.m (115 lb in).
17. Rotate the engine rearward and install the engine mount strut bracket bolts. Refer to «Rotating the Engine for Service Access»(/buick/rendezvous/i-2001-2007/remont/mechanical/#engine-mechanical-34l-la1) in Engine Mechanical - 3.4L.
18. Install the battery ground (negative) cable to the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .

1. Disconnect the battery ground (negative) cable from the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .
2. Remove the torque struts and rotate the engine in order to provide access to remove the generator. Refer to and in Engine Mechanical - 3.6L (LY7).
3. Remove the generator B+ terminal nut and the battery cable from the generator.
4. Disconnect the generator electrical connector.
5. Remove the drive belt from the generator. Refer to «Drive Belt Replacement»(/buick/rendezvous/i-2001-2007/remont/mechanical/#engine-mechanical-repair-instructions-1-of-5-36l-ly7) in Engine Mechanical - 3.6L (LY7).
6. Remove the idler pulley. Refer to «Drive Belt Idler Pulley Replacement»(/buick/rendezvous/i-2001-2007/remont/mechanical/#engine-mechanical-repair-instructions-1-of-5-36l-ly7) in Engine Mechanical - 3.6L (LY7).
7. Remove the generator bolts.
8. Remove the generator from the vehicle.

1. Install the generator to the vehicle.
2. Install the generator bolts. Tighten: Tighten the generator bolts to 50 N.m (37 lb ft).
3. Install the idler pulley. Refer to «Drive Belt Idler Pulley Replacement»(/buick/rendezvous/i-2001-2007/remont/mechanical/#engine-mechanical-repair-instructions-1-of-5-36l-ly7) in Engine Mechanical - 3.6L (LY7).
4. Install the drive belt. Refer to «Drive Belt Replacement»(/buick/rendezvous/i-2001-2007/remont/mechanical/#engine-mechanical-repair-instructions-1-of-5-36l-ly7) in Engine Mechanical - 3.6L (LY7).
5. Connect the generator electrical connector.
6. Install the battery cable and the generator B+ terminal nut to the generator. Tighten: Tighten the generator B+ terminal nut 20 N.m (15 lb ft).
7. Install the torque struts. Refer to and in Engine Mechanical - 3.6L (LY7).
8. Connect the battery ground (negative) cable to the battery. Refer to «Battery Negative Cable Disconnect/Connect Procedure (LA1)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/rendezvous/i-2001-2007/remont/charging-system/#battery-charging-system-and-starting-system) .

Scheme 6

Batteries that are no longer wanted must be disposed of by an approved battery recycler and must never be thrown in the trash or sent to a landfill.

Batteries that are not part of the vehicle itself, not the battery under the hood, must only be transported on public streets for business purposes via approved hazardous material transportation procedures.

Battery storage, charging, and testing facilities in repair shops must meet various requirements for ventilation, safety equipment, material segregation, etc.

The maintenance-free battery is standard. There are no vent plugs in the cover. The battery is completely sealed except for 2 small vent holes in the side. These vent holes allow the small amount of gas that is produced in the battery to escape.

The battery has 3 functions as a major source of energy

1. Engine cranking
2. Voltage stabilizer
3. Alternate source of energy with generator overload

The battery specification label, example below, contains information about the following

1. The test ratings
2. The original equipment catalog number
3. The recommended replacement model number

Scheme 7

Battery Ratings

A battery may have 3 ratings

1. Amp hour
2. Reserve capacity
3. Cold cranking amperage

When a battery is replaced, use a battery with similar ratings. Refer to the battery specification label on the original battery or refer to Battery Usage .

Amp Hour

The amp hour rating of a battery is the amount of time it takes a fully charged battery, being discharged at a constant rate of 1 amperes and a constant temperature of 27°C (80°F), to reach a terminal voltage of 10.5 volts. Refer to Battery Usage for the amp hour rating of the original equipment battery.

Reserve Capacity

Reserve capacity is the amount of time in minutes it takes a fully charged battery, being discharged at a constant rate of 25 amperes and a constant temperature of 27°C (80°F), to reach a terminal voltage of 10.5 volts. Refer to Battery Usage for the reserve capacity rating of the original equipment battery.

Cold Cranking Amperage

The cold cranking amperage is an indication of the ability of the battery to crank the engine at cold temperatures. The cold cranking amperage rating is the minimum amperage the battery must maintain for 30 seconds at -18°C (0°F) while maintaining at least 7.2 volts. Refer to Battery Usage for the cold cranking amperage rating for this vehicle.

Generator

The Valeo SG10 and SG12 generators are electrically similar to earlier models. The generators feature the following major components

1. The delta stator
2. The rectifier bridge
3. The rotor with slip rings and brushes
4. A conventional pulley
5. Dual internal fans
6. The regulator

The pulley and the fan cool the slip ring and the frame.

The generators feature permanently lubricated bearings. Service should only include tightening of mount components. Otherwise, replace the generator as a complete unit.

Regulator

The voltage regulator controls the rotor field current in order to limit the system voltage. When the field current is on, the regulator switches the current on and off at a rate of 400 cycles per second in order to perform the following functions

1. Radio noise control
2. Obtain the correct average current needed for proper system voltage control

At high speeds, the on-time may be 10 percent with the off-time at 90 percent. At low speeds, the on-time may be 90 percent and the off-time 10 percent.

The generator provides voltage to operate the vehicle's electrical system and to charge its battery. A magnetic field is created when current flows through the rotor. This field rotates as the rotor is driven by the engine, creating an AC voltage in the stator windings. The AC voltage is converted to DC by the rectifier bridge and is supplied to the electrical system at the battery terminal.

When the engine is running, the generator turn-on signal is sent to the generator from the engine control module (ECM), turning on the regulator. The generator's voltage regulator controls current to the rotor, thereby controlling the output voltage. The rotor current is proportional to the electrical pulse width supplied by the regulator. When the engine is started, the regulator senses generator rotation by detecting AC voltage at the stator through an internal wire. Once the engine is running, the regulator varies the field current by controlling the pulse width. This regulates the generator output voltage for proper battery charging and electrical system operation. The generator F terminal is connected internally to the voltage regulator and externally to the ECM. When the voltage regulator detects a charging system problem, it grounds this circuit to signal the ECM that a problem exists. The ECM monitors the generator field duty cycle signal circuit. The system voltage sense circuit receives B+ voltage at the body control module (BCM). This voltage is used by the regulator as the reference for system voltage control.

When the ignition switch is turned to RUN, the charge indicator turns on for a few seconds (bulb check), then turns off. The ECM commands the bulb of the charge indicator on by sending a class 2 serial data line message to the instrument panel cluster (IPC) when the ECM detects a charging system problem.

Charge Indicator

The instrument panel cluster (IPC) illuminates the battery indicator in the message center when the following occurs

1. The engine control module (ECM) detects that the generator output is less than 11 volts or greater than 16 volts. The IPC receives a class 2 message from the ECM requesting illumination.
2. The IPC performs the displays test at the start of each ignition cycle. The indicator illuminates for approximately 3 seconds.
3. The ignition is ON, with the engine OFF.

The IPC sends a class 2 message to the radio for audible warning when this indicator is on.

Regulated Voltage Control (RVC)

The LY7 engine comes equipped with GEN II RVC. Regulated voltage control (RVC) is used to more accurately control the amount of voltage put into the battery based upon the battery state of charge (SOC) and battery temperature.

The main components of the RVC system is a new voltage regulator, the body control module (BCM ), and the engine control module (ECM).

1. Voltage regulator - uses a pulse width modulation (PWM) signal on the generator L-terminal circuit instead of a 5-volt reference signal from the ECM to determine voltage output of the generator.
2. ECM - controls the PWM signal to the regulator and provides diagnostics for the generator L-terminal and generator F-terminal. It also provides feedback of the generator F-terminal to the BCM for its calculations.
3. BCM - calculates an estimate of the battery SOC and battery temperature based upon, battery voltage and internal calibrations. When the BCM has determined what voltage the battery should receive, a message is sent to the ECM. This message tells the ECM what percentage to set the PWM signal at.

With RVC in closed loop control of the generator, it can vary the voltage at the battery from 13.4 volts, battery temperature above 70°C (158°F) and battery SOC 95 percent or higher, to 14.9 volts, battery temperature below -30°C (-22°F) and battery SOC 65 percent or lower. If RVC looses control of the generator because of a failure the voltage regulator will default to 13.9 volts at the battery and function as a normal generator.

Circuit Description (LY7)

The generator provides voltage to operate the vehicle's electrical system and to charge its battery. A magnetic field is created when current flows through the rotor. This field rotates as the rotor is driven by the engine, creating an AC voltage in the stator windings. The AC voltage is converted to DC by the rectifier bridge and is supplied to the electrical system at the battery terminal.

When the engine is running, The ECM sends a PWM signal to the voltage regulator. The generator's voltage regulator then controls the current to the rotor according to the PWM signal received, thereby controlling the output voltage. The rotor current is proportional to the electrical pulse width supplied by the regulator. The PWM signal may vary between 12 percent and 88 percent. The lower the PWM signal percentage the lower the generator voltage output will be. Below 12 percent and above 88 percent the voltage regulator defaults to 13.9 volts. This generator is self starting and does not require voltage on the L-terminal circuit to initiate battery charging. This also means that the generator cannot be commanded OFF with the scan tool. When the voltage regulator detects a charging system problem, it grounds the generator L-terminal circuit to signal the ECM that a problem exists. The ECM also monitors the generator field duty cycle signal circuit for failures.

Starting System Description and Operation

The PG-260 D is a non-repairable starter motor. It has pole pieces that are arranged around the armature. Both solenoid windings are energized. The pull-in winding circuit is completed to the ground through the starter motor. The windings work together magnetically to pull and hold in the plunger. The plunger moves the shift lever. This action causes the starter drive assembly to rotate on the armature shaft spline as it engages with the flywheel ring gear on the engine. Moving at the same time, the plunger also closes the solenoid switch contacts in the starter solenoid. Full battery voltage is applied directly to the starter motor and it cranks the engine.

As soon as the solenoid switch contacts close, current stops flowing thorough the pull-in winding because battery voltage is applied to both ends of the windings. The hold-in winding remains energized; its magnetic field is strong enough to hold the plunger, shift lever, starter drive assembly, and solenoid switch contacts in place to continue cranking the engine. When the engine starts, pinion overrun protects the armature from excessive speed until the switch is opened.

When the ignition switch is released from the START position, the CRANK relay opens and battery voltage is removed from the starter solenoid S terminal. Current flows from the motor contacts through both windings to the ground at the end of the hold-in winding. However, the direction of the current flow through the pull-in winding is now opposite the direction of the current flow when the winding was first energized.

The magnetic fields of the pull-in and hold-in windings now oppose one another. This action of the windings, along with the help of the return spring, causes the starter drive assembly to disengage and the solenoid switch contacts to open simultaneously. As soon as the contacts open, the starter circuit is turned off.

Moving the ignition switch to the START position sends a 12 V signal to the PCM Ignition Crank Sense. The PCM then grounds the control circuit, which travels through the Park Neutral Position switch, of the CRANK relay. When the CRANK relay is energized it allows voltage to the starter solenoid S terminal.

Electrical Load Management

Electrical load management is designed to maintain battery voltage and covers more than load-shed. The body control module (BCM) will request increases in idle speed from the powertrain control module (PCM), when the vehicle is in park or neutral, as well as turn off loads in order to manage the electrical system and preserve the vehicle electrical power availability. The BCM calculates the battery temperature, voltage and charging rate at all times while the engine is running.

The BCM calculates the battery temperature by factoring in

1. the current intake manifold air temperature compared to the last temperature recorded when the ignition switch was turned OFF
2. the current battery voltage compared to the last battery voltage recorded when the ignition switch was turned OFF
3. the length of time since the last battery temperature calculation

If the calculated battery temperature is below -15°C (5°F), the BCM institutes steps to control the load.

The BCM makes constant voltage measurements. If the BCM detects a low voltage steps are taken to control the load.

The BCM calculates the net charge rate on the electrical system by making constant voltage measurements and using the measurements to calculate the charge rate in amp/hours. If the BCM detects a negative charge rate for the battery, the BCM institutes steps to control the load.

The BCM will turn off loads, called the load-shed function, in order to preserve the vehicle electrical system operation. The criteria used by the PMM to regulate this electrical load management are outlined below

Load Shed System Description and Operation

Each load management function, either idle boost or load-shed, is discrete. No two functions are implemented at the same time.

During each load management function, the BCM checks the battery temperature, battery voltage and amp-hour calculations and determines if a different power management function should be implemented.

The highest loads on the electrical system are the resistance load of heating elements. The BCM controls the heating elements in the outside rear view mirrors, the rear window and the heated seats, either directly or by sending messages to the module controlling power to these devices.

Idle Boost Functions

The BCM sends a serial data request to the PCM to increase the idle speed. The PCM then adjusts the idle speed by using a special program and idle speed ramp calculations in order to prevent driveability and safety concerns. The idle speed boost and cancel function will vary from one moment to another. This happens because the PCM responds to changes in the inputs from the sensors used to control the powertrain.

Load-Shed

This vehicle uses the following load-shed actions

Load Shed System Description and Operation

Special Tools

Special Tools Illustration Tool Number/Description J 38758 Parasitic Draw Test Switch J 42000 Battery Tester

Scheme 8

Scheme 9

See also:
• Scan Tool Does Not Power Up
• Power Mode Mismatch
• Diagnostic Trouble Code (DTC) List
• Theft Deterrent System Schematics
• Engine Controls Schematics
• Engine Controls Connector End Views
• Testing for Intermittent Conditions and Poor Connections
• Circuit Testing
• Wiring Repairs
• Connector Repairs
• Powertrain Control Module (PCM) Replacement
• Engine Controls Schematics
• Engine Control Module (ECM) Connector End Views
• Checking Aftermarket Accessories
• Keyless Entry System Description and Operation
• Battery Disconnect Caution
• Power Distribution Schematics
• Control Module References
• Instrument Panel Cluster (IPC) Replacement
• Drive Belt Replacement
• Master Electrical Component List
• Ignition Switch Replacement
• Engine Will Not Crank - Crankshaft Will Not Rotate
• Lifting and Jacking the Vehicle
• Radiator Air Baffle Assemblies and Deflectors
• Fastener Notice
• Brace Replacement - Front Fender Upper Diagonal - Right
• Torque Converter Cover Replacement (LA1)
• Power Steering Pump Replacement (LA1 )
• Drive Belt Replacement
• Diagnostic System Check - Engine Electrical
• Symptoms - Engine Electrical
• Diagnostic Trouble Code (DTC) List
• Charging System Test
• Engine Electrical Connector End Views
• Starting System Description and Operation
• Starter Solenoid Does Not Click
• Engine Cranks Slowly
• Charge Indicator Always On
• Charge Indicator Inoperative
• Battery Common Causes of Failure
• Battery Usage
• Battery Replacement
• Generator Usage