Generators & Regulators: Other Dodge Durango II

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 Powertrain Control Module (PCM). The EVR is not serviced separately. If replacement is necessary, the PCM must be replaced.

The BTS is 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 to vary the battery charging rate. System voltage will be higher at cold 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 AC current to 3 positive and 3 negative diodes for rectification. From the diodes, rectified DC current is delivered to the vehicle electrical system through the generator battery terminal.

Although the generators appear the same externally, different generators with different 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 defective stator or diode.

The amount of DC 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. See BATTERY TEMPERATURE SENSOR . It then determines a target charging voltage. If sensed battery voltage is .5 volts 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.

PCM/SKREEM

Note. Before replacing the PCM, be certain to check the related component/circuit integrity for failures not detected due to a double fault in the circuit. Most PCM driver/control circuit failures are caused by internal component failures (i.e. relays 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 DTC has been set.

When a PCM and the Sentry Key Remote Entry Module (SKREEM) on vehicles equipped with the SKIS are replaced at the same time, perform the following steps in order

1. Program the new PCM.
2. Program the new SKREEM (also sometimes referred to as the Wireless Control Module or WCM).
3. Replace all ignition keys and program them into the new SKREEM/WCM.

Note. Be certain to enter the correct country code for the SKREEM/WCM. If the incorrect country code is programmed into the SKREEM, it cannot be changed and the SKREEM must be replaced.

Note. If the PCM and the SKREEM/WCM are replaced at the same time, all vehicle ignition keys will need to be replaced and new keys programmed into the new SKREEM/WCM.

The SKIS secret key is an ID code that is unique to each SKREEM/WCM. This code is programmed and stored in the SKREEM/WCM, the PCM, and each ignition key transponder chip. When the PCM or SKREEM/WCM is replaced, it is necessary to program the Secret Key into the new module using a diagnostic scan tool. Follow the programming steps outlined in the diagnostic scan tool for "PCM Replaced" or "WCM Replaced" under "Miscellaneous Functions" for the "WCM/Wireless Control Module" menu item as appropriate.

SKIM

1. Turn the ignition switch to the ON position (transmission in Park/Neutral).
2. Use the DRBIII(R) and select THEFT ALARM, SKIM, then MISCELLANEOUS.
3. Select PCM 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 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 to the SKIM).
8. Program ignition keys to the SKIM.

IGNITION KEYS

Each ignition key transponder also has a unique ID code that is assigned at the time the key is manufactured. When a key is programmed into the SKREEM/WCM, follow the programming steps outlined in the diagnostic scan tool for "Program Ignition Keys or Key FOB's" under "Miscellaneous Functions" for the "WCM/Wireless Control Module" menu item.

Note. A maximum of 8 keys can be learned to each SKREEM. Once a key is learned to a SKREEM, that key has acquired the Secret Key for that SKREEM and cannot be transferred to any other SKREEM or vehicle.

If ignition key programming is unsuccessful, the DRBIII(R) will display one of the following error messages

1. Programming Not Attempted The DRBIII(R) attempts to read the programmed key status and there are no keys programmed into SKIM memory.
2. Programming Key Failed (Possible Used Key From Wrong Vehicle) SKIM is unable to program an ignition key transponder due to one of the following: The ignition key transponder is faulty. The ignition key transponder is or has already been programmed to another vehicle.
3. 8 Keys Already Learned, Programming Not Done The SKIM transponder ID memory is full.
4. Learned Key In Ignition The ID for the ignition key transponder currently in the ignition lock cylinder is already programmed in SKIM memory.

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 Conditions

This code is set when engine off time is greater than 480 minutes. Ambient temperature is greater than 38°F (3°C). After a calibrated amount of cool down time, the PCM compares the ECT sensor, IAT sensor, and the Ambient Temp sensor values. If the IAT sensor value is not within 18°F (-7.7°C) of the other 2 temperature sensors, DTC P0071 is set. DTC is a two trip fault. Three good trips turn off the MIL.

Possible Causes

1. (G31) AAT sensor signal circuit shorted to battery voltage.
2. (G31) AAT sensor signal circuit open.
3. (G931) Sensor ground circuit open.
4. (G31) AAT sensor signal shorted to ground.
5. (G31) AAT sensor signal circuit shorted to the (G931) sensor ground circuit.
6. Ambient air temperature sensor.
7. Front Control Module (FCM).

When Monitored & Set Condition

This code is monitored with the ignition key on. DTC P0072 is set when ambient temperature sensor is less than .078 volt at the PCM for 2.8 seconds. DTC is a one trip fault. Three good trips turn off the MIL.

1. (G31) AAT sensor signal circuit shorted to ground.
2. (G31) AAT sensor signal circuit shorted to the (G931) sensor ground circuit.
3. Ambient air temperature sensor.
4. Front Control Module (FCM).

This code is monitored with the ignition on. DTC P0073 sets when the ambient temperature sensor voltage is greater than 4.98 volts at the PCM for 2.8 seconds. DTC is a one trip fault. Three good trips turn off the MIL.

1. (G31) AAT sensor signal circuit shorted to battery voltage.
2. (G31) AAT sensor signal circuit open.
3. (G931) Sensor ground circuit open.
4. Ambient air temperature sensor.
5. Front Control Module (FCM).

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

1. (K25) Batt temp signal circuit shorted to ground.
2. (K25) Batt temp signal circuit shorted to (K91) Batt temp return circuit.
3. Battery temperature sensor.
4. Front Control Module (FCM).

This code is monitored with ignition on and battery voltage greater than 10 volts. DTC P0519 is set when battery temperature voltage is above 4.94 volts. DTC is a one trip fault. Three good trips turn off the MIL.

1. (K25) Batt temp sensor signal circuit shorted to battery voltage.
2. (K25) Batt temp signal circuit open.
3. (K91) Batt temp return circuit open.
4. Battery temperature sensor.
5. Front Control Module (FCM).

This code is monitored with the engine running at 1000 RPM or greater. DTC P0562 is set when battery voltage is one volt less than desired system voltage for a set period of time. DTC is a one trip fault. ETC light is flashing.

1. Resistance in the (A1) battery positive circuit.
2. Resistance in the generator case ground.
3. Generator operation.
4. (K20) Generator field control circuit open.
5. (K20) Generator field control circuit shorted to ground.
6. (Z20) Ground circuit open.
7. PCM.

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

1. (K20) Generator field control circuit shorted to battery voltage.
2. Generator.
3. PCM.

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

1. (K20) Gen field control circuit shorted to battery voltage.
2. (K20) Gen field control circuit open.
3. (K20) Gen field control circuit shorted to ground.
4. (Z20) Ground circuit open.
5. Generator.
6. PCM.

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

1. Excessive resistance in the battery positive circuit.
2. Excessive resistance in the case ground.
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) Gen ground circuit open.
7. Generator.
8. PCM.

INTERMITTENT CONDITION

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 scan tool freeze frame data. 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 the 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 a voltage drop test 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 evaporative emission trouble codes, perform a visual and physical inspection of the related parts including hoses and the fuel filler cap.
11. 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.
12. Use the scan tool to perform a system test if one applies to failing component.
13. A data recorder, and/or lab scope and an assistant should be used to help diagnose intermittent conditions.
14. If any problems were found during the above inspections, repair as necessary. Perform «POWERTRAIN VERIFICATION TEST VER-5»(ref-166557-S35640678772004092300000) under VERIFICATION TESTS. If no problems were found, test is complete.