I have this errors code to this car.p1637,p1638,p1699 and p1260.i change the batery and check all conectors .any ideea please?

DTC P1637

The powertrain control module (PCM) / engine control module (ECM) uses the charge indicator control circuit, and the generator 2 turn on signal circuit on diesels with dual generators, to control the generator(s). A high side driver within the PCM/ECM allows the PCM/ECM to turn the generator ON and OFF. When generator operation is desired, the PCM/ECM sends a 10-11 volts-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/ECM, the voltage regulator controls generator output independently of the PCM/ECM. Under certain operating conditions, the PCM/ECM can turn OFF the generator by turning OFF the voltage on the charge indicator control circuit. The PCM/ECM has fault detection circuitry which monitors the state of the charge indicator control circuit. If the fault detection circuit senses a voltage other than what is expected, the charge indicator will turn ON and this DTC will set. The voltage regulator also contains fault detection circuitry. If the regulator detects a problem, the regulator will ground the charge indicator control circuit, pulling the voltage low. This also causes the charge indicator to turn ON and the PCM/ECM to set the DTC.

What engine is in your truck ?

DTC P1638

The powertrain control module (PCM) uses the generator field duty cycle signal circuit to monitor the duty cycle of the generator. 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 PCM uses the PWM signal input to determine the generator load on the engine. This allows the PCM to adjust the idle speed to compensate for high electrical loads.
The PCM monitors the state of the generator field duty cycle signal circuit. When the key is in the RUN position and the engine is OFF, the PCM should detect a duty cycle near 0 percent. However, when the engine is running, the duty cycle should be between 5-100 percent. The PCM monitors the PWM signal using a key ON test and a RUN test. During the tests, if the PCM detects an out of range PWM signal, DTC P1638 will set. When the DTC sets, the PCM will send a class 2 serial data message to the IPC to illuminate the charge indicator.

DTC P1638
The powertrain control module (PCM) uses the generator field duty cycle signal circuit to monitor the duty cycle of the generator. 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 PCM uses the PWM signal input to determine the generator load on the engine. This allows the PCM to adjust the idle speed to compensate for high electrical loads.
The PCM monitors the state of the generator field duty cycle signal circuit. When the key is in the RUN position and the engine is OFF, the PCM should detect a duty cycle near 0 percent. However, when the engine is running, the duty cycle should be between 5-100 percent. The PCM monitors the PWM signal using a key ON test and a RUN test. During the tests, if the PCM detects an out of range PWM signal, DTC P1638 will set. When the DTC sets, the PCM will send a class 2 serial data message to the IPC to illuminate the charge indicator.

Diagnostic Aids
• DTCs P1637 and P1638 may set at the same time depending on the failure.
• Use a scan tool in order to diagnosis the generator circuits. The scan tool should display Inactive for the L terminal and 10-40 percent for the F terminal when the ignition is ON. When the engine is operating, the display should indicate that the L terminal is Active and the F terminal is more than 10 percent.
• A generator fault, such as a shorted output diode, malfunctioning regulator, open or shorted rotor, or open sense lead or battery feed may cause a low battery charge. Refer to Charging System Test for further information and generator diagnosis.

If these codes are being only set during start I would expect a failure of the battery. If the voltage goes much below 9 VDC the computers (EMS) can become erratic and codes and limp home modes are a common result of defective and discharged batteries!



Careful having the battery tested. Any arcing etc at the battery can be the kiss of death for the engine computer. Better to remove terminal to check. Or test the crank voltage with multi-meter.

P1699 No CCD/J1850 Messages Received From The Climate Control Module (CCM)

Are you having any trouble with heater/AC controls?

P1699 No CCD/J1850 Messages Received From The Climate Control Module (CCM) this should not have anything to do with your emission test. Suggest taking to your local auto parts dealer that will pull the codes from your OBDII for free, check your phone book and call them to ask if they offer this service. most national stores will do it because they will then sell you the parts and give advice on repairs

They are manufactures codes,not generic

Without a factory work shop manual &
emission & diagnostic manuals,which
you need to buy & have, to work on your
own vehicles

Your left with the choice of a repair shop or dealer

P1638 Instrument to ECM , CAN (control area network) short circuit failure,this is either the instrument panel at fault or the ECM.Basically its a open wire. between ECM and instrument panel

This problem is normally associated with a failure of an ecu/can bus output, in many instances it is also associated with anouther problem being present, Air Con not operating correctly is a favorite. The best bet is to narrow the problem down try and locate what else isn't working and this will guide you to the cause problem. Problems can be anything from a faulty ECU to a blown fuse.

CODE P1637 - GENERATOR L TERMINAL CIRCUIT MALFUNCTION CONDITIONS. CODE P1638 - GENERATOR F TERMINAL CIRCUIT MALFUNCTION CONDITIONS. POSSIBLE CAUSES FAULTY GENERATOR WHICH IS ALTERNATOR.CHECK GENERATOR POWER FEED WIRES AND CHECK GENERATOR VOLTAGE REGULATOR WIRES FOR LOOSENESS AND DAMAGE. MAKE SURE BATTERY VOLTS ARE 12.6 VOLTS. IF BATTERY WEAK DUE BAD GENERATOR VECHICLE WONT START.