Charging System - Generators & Regulators: Other Dodge Pickup R2500

BATTERY TEMPERATURE SENSOR

The Battery Temperature Sensor (BTS) is attached to the battery tray located under the battery.

The generator is belt-driven by the engine using a serpentine type drive belt. It is serviced only as a complete assembly. If the generator fails for any reason, the entire assembly must be replaced.

VOLTAGE REGULATOR

The Electronic Voltage Regulator (EVR) is not a separate component. It is actually a voltage regulating circuit located within the PCM (within the ECM for diesel engines). The EVR is not serviced separately. If replacement is necessary, the PCM must be replaced.

The charging system is turned on and off with the ignition switch. The system is on when the engine is running and the ASD relay is energized. When the ASD relay is on, voltage is supplied to the ASD relay sense circuit at the PCM (ECM on diesel). This voltage is connected through the PCM (ECM on diesel) and supplied to one of the generator field terminals (Gen. Source +) at the back of the generator.

The amount of direct current produced by the generator is controlled by the EVR (field control) circuitry contained within the PCM (ECM on diesel). This circuitry is connected in series with the second rotor field terminal and ground.

A battery temperature sensor, located in the battery tray housing, is used to sense battery temperature. This temperature data, along with data from monitored line voltage, is used by the PCM (ECM on diesel) to vary the battery charging rate. This is done by cycling the ground path to control the strength of the rotor magnetic field. The PCM then compensates and regulates generator current output accordingly.

All vehicles are equipped with On-Board Diagnostics (OBD). All OBD-sensed systems, including EVR (field control) circuitry, are monitored by the PCM (ECM on diesel). Each monitored circuit is assigned a Diagnostic Trouble Code (DTC). The PCM will store a DTC in electronic memory for certain failures it detects.

The Check Gauges Lamp (if equipped) monitors: Charging system voltage, engine coolant temperature and engine oil pressure. If an extreme condition is indicated, the lamp will be illuminated. this is done as a reminder to check the 3 gauges. The signal to activate the lamp is sent via the CCD bus circuits. The lamp is located on the instrument panel.

The BTS used to determine the battery temperature and control battery charging rate. This temperature data, along with data from monitored line voltage, is used by the PCM (ECM on diesel) to vary the battery charging rate. System voltage will be higher at colder temperatures and is gradually reduced at warmer temperatures.

The PCM sends 5 volts to the sensor and is grounded through the sensor return line. As temperature increases, resistance in the sensor decreases and the detection voltage at the PCM increases.

The BTS is also used for OBDII diagnostics. Certain faults and OBDII monitors are either enabled or disabled, depending upon BTS input (for example, disable purge and enable Leak Detection Pump (LDP) and O2 sensor heater tests). Most OBDII monitors are disabled below 20°F (-6.7°C).

As the energized rotor begins to rotate within the generator, the spinning magnetic field induces a current into the windings of the stator coil. Once the generator begins producing sufficient current, it also provides the current needed to energize the rotor.

The stator winding connections deliver the induced alternating current to 3 positive and 3 negative diodes for rectification. From the diodes, rectified direct current is delivered to the vehicle electrical system through the generator battery terminal.

Although the generators appear the same externally, different generators with difference output ratings are used on this vehicle. Be certain that the replacement generator has the same output rating and part number as the original unit.

Noise emitting from the generator may be caused by: worn, loose or defective bearings; a loose or defective drive pulley; incorrect, worn, damaged or misadjusted fan drive belt; loose mounting bolts; a misaligned drive pulley or a defective stator or diode.

The amount of direct current produced by the generator is controlled by EVR circuitry contained within the PCM. This circuitry is connected in series with the generators second rotor field terminal and its ground.

Voltage is regulated by cycling the ground path to control the strength of the rotor magnetic field. The EVR circuitry monitors system line voltage (B+) and battery temperature. It then determines a target charging voltage. If sensed battery voltage is .5 volt or lower than the target voltage, the PCM grounds the field winding until sensed battery voltage is .5 volts above target voltage. A circuit in the PCM cycles the ground side of the generator field up to 100 times per second (100 Hz), but has the capability to ground the field control wire 100 percent of the time (full field) to achieve the target voltage. If the charging rate cannot be monitored (limp-in), a duty cycle of 25 percent is used by the PCM in order to have some generator output.

PROGRAMMING

Note. There are 2 procedures for transferring the secret key to the SKIM. When ONLY the SKIM module is replaced, the secret key is transferred from the PCM to the SKIM. The ORIGINAL KEYS may then be programmed to the SKIM. When ONLY the PCM is replaced, then the secret key is transferred from the SKIM to the PCM. The ORIGINAL KEYS may be used. When BOTH the SKIM and the PCM are replaced, the secret key is transferred from the SKIM to the PCM, and NEW KEYS must be programmed.

Note. Before replacing the Powertrain Control Module (PCM) for a failed driver, control circuit, or ground circuit, or ground circuit, be sure to check the related component/circuit integrity for failures not detected due to a double fault in the circuit. Most PCM driver/control circuit features are caused be internal component failures (i.e.; relay and solenoids) and shorted circuits (i.e.; pull-ups, drivers and switched circuits). These failures are difficult to detect when a double fault has occurred and only one Diagnostic Trouble Code (DTC) has set.

When a PCM (SBEC) and Sentry Key Immobilizer Module (SKIM) are replaced at the same time perform the following steps in order

1. Program the new PCM (SBEC).
2. Program the new SKIM.
3. Replace all ignition keys and program them to the new SKIM.

PCM (SBEC)

The Sentry Key Immobilizer System (SKIS) Secret Key is an ID code that is unique to each SKIM. This code is programmed and stored in the SKIM, PCM and transponder chip (ignition keys). When replacing the PCM it is necessary to program the secret key into the new PCM using the DRBIII(R) scan tool. Perform the following steps to program the secret key into the PCM.

1. Turn the ignition switch on (transmission in Park/Neutral).
2. Use the DRBIII(R) scan tool and select THEFT ALARM, SKIM then MISCELLANEOUS.
3. Select PCM REPLACED (GAS ENGINE).
4. Enter secured access mode by entering the vehicle 4-digit PIN.
5. Select ENTER to update PCM VIN.
6. Press ENTER to transfer the secret key (the SKIM will send the secret key to the PCM).
7. Press PAGE BOOK to get to the SELECT SYSTEM menu and select ENGINE, MISCELLANEOUS, and SRI MEMORY CHECK.
8. The DRBIII(R) scan tool will ask, "Is odometer reading between XX and XX? Select the YES or NO button on the DRBIII(R) scan tool. If NO is selected, the DRBIII(R) scan tool will read, ENTER ODOMETER READING (FROM I.P. ODOMETER). Enter odometer reading from the instrument cluster and press ENTER.

SKIM

1. Turn the ignition switch on (transmission in Park/Neutral).
2. Use the DRBIII(R) scan tool and select THEFT ALARM, SKIM then MISCELLANEOUS.
3. Select SKIM REPLACED (GAS ENGINE).
4. Program the vehicle 4-digit PIN into SKIM.
5. Select COUNTRY CODE and enter the correct country.
6. Select YES to update the VIN (the SKIM will learn the VIN from the PCM).
7. Press ENTER to transfer the secret key (the PCM will send the secret key information to the SKIM).
8. Program ignition keys to the SKIM.

IGNITION KEYS TO SKIM

1. Turn the ignition switch on (transmission in Park/Neutral).
2. Use the DRBIII(R) scan tool and select THEFT ALARM, SKIM then MISCELLANEOUS.
3. Select PROGRAM IGNITION KEY'S.
4. Enter secured access mode by entering the vehicle 4-digit PIN.
5. If ignition key programmed is unsuccessful, the DRBIII(R) scan tool will display one of the following messages: Programming Not Attempted The DRBIII(R) scan tool attempts to read the programmed key status and there are no keys programmed into SKIM memory. Programming Key Failed (Possible Used Key From Wrong Vehicle) SKIM is unable to program key due to a faulty ignition key transponder or ignition key is programmed to another vehicle. 8 Keys Already Learned, Programming Not Done SKIM transponder ID memory is full. Learned Key In Ignition Ignition key transponder ID is currently programmed in SKIM memory.
6. Obtain ignition keys to be programmed from customer (8 keys maximum).
7. Using the DRBIII(R) scan tool, erase all ignition keys by selecting MISCELLANEOUS and ERASE ALL CURRENT IGN. KEYS.
8. Program all ignition keys.

BELT TENSION

BELT ADJUSTMENT SPECIFICATIONS

Blank Message Screen

Check for loose cable connections or faulty cable. If cable connections and cable are okay, check voltage at Data Link Connector (DLC) terminal No. 16 (Pink wire). Voltage should be at least 11 volts. If voltage is not as specified, check wiring circuit and necessary fuses.

NO RESPONSE Message

If scan tool displays NO RESPONSE from Powertrain Control Module (PCM), repair communication concern. See appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.

When Monitored & Set Condition

This code is monitored with the ignition ON and no battery temperature sensor open or short faults present. DTC P0071 sets after 5 warm-up cycles have occurred (coolant increases at least 40°F (22°C) to a minimum of 160°F (71°C) and the odometer mileage has increased 196.6 miles and the battery temperature has changed less than 7.2°F (4°C) change in temperature. One trip fault.

Possible Causes

1. Good trip equal to zero.
2. (K118) battery temp signal circuit shorted to voltage.
3. Battery temperature sensor.
4. Resistance in the (K118) battery temp sensor signal circuit.
5. Resistance in the (K4) sensor ground circuit.
6. (K118) battery temp sensor signal circuit shorted to ground.
7. PCM.

When Monitored & Set Conditions

This code is monitored while the engine is running. This code sets when the ECM does not read a change in value from the sensor over time.

1. Battery temperature sensor.
2. Intermittent condition.

This code is monitored with the ignition on and battery voltage greater than 10.4 volts. This code sets when the circuit voltage to the ECM falls below a calibrated threshold for a certain period of time.

1. Battery temperature sensor.
2. Signal circuit shorted to ground.
3. Signal circuit shorted.
4. 5-volt supply shorted to voltage.
5. Intermittent condition.
6. ECM.

This code is monitored with the ignition on and battery voltage greater than 10 volts. DTC P0516 is set when battery temperature sensor voltage is below .039 volt. One trip fault. Three good trips to turn off the MIL.

1. Battery temp volts below .5 volt.
2. Battery temperature sensor.
3. (K118) batt temp signal circuit shorted to ground.
4. (K118) batt temp signal circuit shorted to (K4) sensor ground circuit.
5. PCM.

This code is monitored with ignition on and battery voltage greater than 10 volts. DTC P0517 sets when battery temperature voltage is above 4.94 volts. One trip fault. Three good trips to turn off the MIL.

1. Battery temp sensor voltage above 4.8 volts.
2. Battery temperature sensor.
3. (K118) batt temp signal circuit shorted to voltage.
4. (K118) batt temp signal circuit open.
5. (K4) sensor ground circuit open.
6. PCM.

This code is monitored with the key on or the engine running. DTC P0562 is set when battery voltage at Powertrain Control Module (PCM) is less than 6 volts.

1. P0622 present.
2. P2502 present.
3. P2503 present.
4. Battery terminal connections.
5. Accessory wiring.
6. Battery.
7. High resistance in wire harness.
8. ECM.
9. Intermittent condition.

This code is monitored with the engine running. The engine speed greater than 1000 RPM. DTC P0562 sets when battery voltage is 1 volt less than desired voltage for a set period of time. One trip fault. ETC light is flashing.

1. Good trip equal to zero.
2. Resistance in the battery positive circuit.
3. Resistance in the generator ground.
4. Generator operation.
5. (K20) gen field control circuit open.
6. (K20) gen field control circuit shorted to ground.
7. Ground circuit open.
8. PCM.

This code is monitored with the key ON or the engine running. DTC P0563 sets when the battery voltage detected by the ECM is greater than a calibrated value.

1. P0622 present.
2. P2502 present.
3. P2504 present.
4. Batteries improperly installed.
5. ECM.
6. Intermittent condition.

This code is monitored with the ignition on. Engine RPM greater than 1000 RPM. With no other charging system codes set. DTC P0563 is set when battery voltage is 1 volt greater than desired voltage. Battery voltage greater than 15.75 volts. One trip fault. Three good trips to turn off the MIL.

1. Good trip equal to zero.
2. Generator operation.
3. (K20) gen field control circuit shorted to voltage.
4. PCM.

This DTC is monitored with the ignition key ON and the engine running. DTC P0622 sets when the PCM tries to regulate the generator field with no result during monitoring.

1. Generator field performance.
2. (K125) gen field source circuit open.
3. (K20) gen field control circuit open.
4. (K20) gen field control circuit shorted to ground.
5. Generator.
6. PCM.

This code is monitored with the ignition on and the engine running. DTC P0622 is set when the PCM tries to regulate the generator field with no result during monitoring. One trip fault. Three good trips to turn off the MIL.

1. Good trip equal to zero.
2. Generator operation.
3. (K20) gen field control circuit shorted to voltage.
4. (K20) gen field control circuit open.
5. (K20) gen field control circuit shorted to ground.
6. (Z346) ground circuit open.
7. PCM.

This code is monitored when the ignition is ON. DTC P0622 sets when the feedback signal does not match the commanded signal for the voltage regulator.

1. Generator.
2. Open driver circuit.
3. Gen source shorted to battery negative.
4. Field driver circuit shorted to voltage.
5. Gen source open.
6. ECM.

The code is monitored with the ignition key on. DTC P1492 is set when the PCM senses the voltage from the battery temperature sensor above 4.9 volts for 3 seconds.

1. Battery temp sensor voltage above 4.8 volts.
2. Battery temperature sensor.
3. (K118) batt temp signal circuit shorted to voltage.
4. (K118) batt temp signal circuit open.
5. (K4) sensor ground circuit open.
6. PCM.

This code is monitored with the ignition on. The Powertrain Control Module (PCM) senses voltage from ambient battery temperature sensor to be less than 0.5 volts for 3 seconds.

1. Battery temp sensor volts below .5 volt.
2. Battery temp sensor.
3. (K118) batt temp signal circuit shorted to ground.
4. (K118) batt temp signal circuit shorted to the (K4) sensor ground.
5. PCM.

Monitored with the ignition key on and the engine speed greater than 0 RPM. When the PCM regulates the generator field and there are no detected field problems, but the voltage output does not decrease.

1. Charging system operation.
2. (K20) generator field control circuit shorted to ground.
3. Generator field coil shorted to ground.
4. Battery temperature sensor.
5. PCM.

This code is monitored with the ignition key on and the engine running over 1500 RPM after 25 seconds. When the PCM regulates the generator field and there are no detected field problems, but the voltage output does not increase.

1. Charging voltage below 15.1 volts.
2. Battery temperature sensor.
3. Resistance in the battery positive circuit.
4. (K125) generator field source circuit open.
5. Resistance in the generator ground.
6. (K125) generator field source circuit shorted to ground.
7. (K20) generator field control circuit open.
8. Resistance in the generator field open.
9. Resistance in the generator field coil.
10. PCM.

This code is monitored with the engine running. The engine speed greater than 1157 RPM. DTC P2503 is set when the battery sensed voltage is 1 volt below the charging goal for 13.47 seconds. The PCM senses the battery voltage turns off the field driver and senses the battery voltage again. If the voltages are the same, the code is set. One trip fault. Three good trips to turn off the MIL.

1. Good trip counter equal to zero.
2. Excessive resistance in the battery positive circuit.
3. Excessive resistance in the case ground.
4. Generator operation.
5. (K20) gen field control circuit shorted to voltage.
6. (K20) gen field control circuit open.
7. (K20) gen field control circuit shorted to ground.
8. (Z346) gen ground circuit open.
9. PCM.

Diesel

Note. The conditions that set the DTC are not present at this time. The following list may help in identifying the intermittent condition.

1. Refer to any TSB's that may apply.
2. Review the DRBIII(R) Freeze Frame information. If possible, try to duplicate the conditions under which the DTC set.
3. With the engine running at normal operating temperature, monitor the DRBIII(R) parameters related to the DTC while wiggling the wire harness. Look for parameter values to change and/or a DTC to set.
4. Visually inspect the related wire harness. Look for an chafed, pierced, pinched, partially broken wires and broken, bent, pushed out, or corroded terminals.
5. Inspect and clean all ECM, engine, and chassis grounds that related to the DTC set.
6. If numerous trouble codes were set, use a wire schematic to help you find any common ground or supply circuits.
7. For any related DTC's, actuate the relay with the DRBIII(R) and wiggle the related wire harness to try to interrupt the actuation.
8. A data recording, and/or lab scope should be used to help diagnose intermittent conditions.
9. Use the DRBIII(R) to perform a system test if one applies to failing component.
10. If problems were found during the inspections, repair as necessary. See «POWERTRAIN VERIFICATION TEST VER-5 (DIESEL)»(ref-165616-S22828287632004083100000) . If no problems were found, test is complete.

Gas

Note. The conditions that set the DTC are not present at this time. The following list may help in identifying the intermittent condition.

1. Refer to any TSB's that may apply.
2. Review the DRBIII(R) Freeze Frame information. If possible, try to duplicate the conditions under which the DTC set.
3. With the engine running at normal operating temperature, monitor the DRBIII(R) parameters related to the DTC while wiggling the wire harness. Look for parameter values to change and/or a DTC to set.
4. Visually inspect the related wire harness. Look for an chafed, pierced, pinched, partially broken wires and broken, bent, pushed out, or corroded terminals.
5. Inspect and clean all PCM, engine, and chassis grounds that related to the DTC set.
6. If numerous trouble codes were set, use a wire schematic to help you find any common ground or supply circuits.
7. For any related DTC's , actuate the relay with the DRBIII(R) and wiggle the related wire harness to try to interrupt the actuation.
8. For intermittent Evaporative Emission trouble codes, perform a visual and physical inspection of the related parts including hoses and the fuel filler cap.
9. For intermittent Misfire DTC's check for restrictions in the intake and exhaust system, improper installation of sensors, vacuum leaks, and binding components driven by the accessory drive belt.
10. A co-pilot, data recording, and/or lab scope should be used to help diagnose intermittent conditions.
11. Use the DRBIII(R) to perform a system test in one applies to failing component.
12. If any problems were found during the above inspection, repair as necessary. See «POWERTRAIN VERIFICATION TEST VER-5 (GAS)»(ref-165616-S23555402112004083100000) . If no problems were found, test is complete.

NGC

Note. The conditions that set the DTC are not present at this time. The following list may help in identifying the intermittent condition.

1. Refer to any TSB's that may apply.
2. Review the DRBIII(R) Freeze Frame information. If possible, try to duplicate the conditions under which the DTC set.
3. With the engine running at normal operating temperature, monitor the DRBIII(R) parameters related to the DTC while wiggling the wire harness. Look for parameter values to change and/or a DTC to set.
4. Turn ignition off.
5. Visually inspect the related wire harness. Disconnect all the related harness connectors. Look for any chafed, pierced, pinched, partially broken wires and broken, bent pushed out, or corroded terminals.
6. Perform «VOLTAGE DROP TEST»(ref-165616-S31361371262004083000000) on the related circuits between the suspected faulty component and the PCM.
7. Inspect and clean all PCM, engine, and chassis grounds that are related to the most current DTC.
8. If numerous trouble codes were set, use a wire schematic and look for any common ground or supply circuits.
9. For any relay DTC's, actuate the relay with the DRBIII(R) and wiggle the related wire harness to try to interrupt the actuation.
10. For intermittent Misfire DTC's, check for restrictions in the intake and exhaust system, proper installation of sensors, vacuum leaks, and binding components that are run by the accessory drive belt.
11. Use the DRBIII(R) to perform a system test if one applies to failing component.
12. A co-pilot, data recorder, and/or lab scope should be used to help diagnose intermittent conditions.
13. If any problems were found during the above inspections, repair as necessary. See «POWERTRAIN VERIFICATION TEST VER-5 (NGC)»(ref-165616-S11782035452004083100000) . If no problems were found, test is complete.