Pinpoint Test B: DTC B1318, B1676, P0562 and/or P1397

Pinpoint Test





Pinpoint Test B: DTC B1318, B1676, P0562 and/or P1397



NOTE: DTC B1318, B1676, P0562 or P1397 can be set if the vehicle has been recently jump started, the battery has been recently charged or the battery has been discharged. The battery may become discharged due to excessive load(s) on the charging system from aftermarket accessories or if vehicle accessories have been operating for an extended period of time without the engine running.

NOTE: Vehicles equipped with the diesel engine shut down strategy and Circuit Deactivation Ignition Module (CDIM) should be tested to confirm that the CDIM (Circuit Deactivation Ignition Module) shuts off the ignition when the PCM shuts off the idle for emission purposes. Failure of the CDIM (Circuit Deactivation Ignition Module) to shut off the ignition during idle shut down would result in a low or discharged battery. Refer to Steering Column for further information.

Normal Operation

With the engine running, the charging system supplies voltage to the battery and the vehicle electrical system through the battery B+ cable. The voltage that is supplied to the vehicle electrical system is used for the operation of vehicle and the various modules. Many modules monitor this voltage and if it drops below a calibrated setpoint, a DTC is set.





This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Engine, generator and battery grounds

- Positive battery cable

- Battery

- Abnormal ignition-off current drain(s)

- Generator

PINPOINT TEST B : DTC B1318, B1676 AND/OR P1397

NOTE: Make sure battery voltage is greater than 12.2 volts prior to and during this pinpoint test.

NOTE: Do not have a battery charger attached during vehicle testing.

B1 CHECK THE BATTERY CONDITION

- Carry out the Battery- Condition Test to determine if the battery can hold a charge and is OK for use. Pinpoint Tests

Does the battery pass the condition test?

Yes
GO to B2.

No
INSTALL a new battery. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

B2 CHECK THE VEHICLE GROUNDS

- Start and idle the engine.

- With the engine running at idle, headlamps ON and the heater blower set to HIGH, measure the voltage drop between the generator housing and the negative battery terminal.





Is the voltage drop less than 0.25 volt (250 mV)?

Yes
GO to B3.

No
INSPECT and REPAIR the engine ground, generator ground or the battery ground for corrosion. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

B3 CHECK THE VOLTAGE DROP IN THE B+ CIRCUIT

- With the engine running at idle, headlamps ON and the heater blower set to HIGH, measure the voltage drop between generator B+ C102B, circuit SDC14 (RD) (gas) or C1104B, circuit SDC14 (RD) (diesel) and the positive battery terminal.





Is the voltage drop less than 0.5 volt?

Yes
GO to B4.

No
INSPECT and REPAIR any corrosion in the B+ SDC14 (RD) or positive battery cable connections. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

B4 CHECK FOR CURRENT DRAINS

- Carry out the Battery- Drain Testing component test. Component Tests and General Diagnostics

Are any circuits causing excessive current drains?

Yes
REPAIR as necessary. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
No problems found at this time. CHECK with the customer to determine if any electrical system(s) may have been accidentally left on. If nothing unusual is found, CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation. GO to Pinpoint Test D to continue diagnosis of the charging system. Pinpoint Test D: DTCs P0625 and P0626