2012 Jeep Wrangler JK Factory Service Manual 28 - DTC-Based Diagnostics

P0562-BATTERY VOLTAGE LOW

P0562-BATTERY VOLTAGE LOW



For a complete wiring diagram, refer to the Wiring Information.


Theory of Operation

The Transmission Control Module (TCM) monitors ignition voltage. The DTC will set if the monitored battery voltage drops below 8.5 volts and a temporary limp in will be activated. If the voltage rises above 9.0 volts, normal operations is resumed and the TCM will record the DTC as a one trip fault. The DTC will only mature to a full DTC if the voltage is less than 8.5 volts with an engine speed greater than 2000 RPM for a least 60 seconds.



Possible Causes

ENGINE CHARGING SYSTEM DTCS
LOW BATTERY VOLTAGE
(A1) B (+) CIRCUIT HIGH RESISTANCE
(Z916) GROUND CIRCUIT HIGH RESISTANCE
(T16) FUSED TRANSMISSION RELAY OUTPUT CIRCUIT HIGH RESISTANCE
TRANSMISSION RELAY
TRANSMISSION CONTROL MODULE (TCM)

Always perform the NAG1 Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure).


1. CHECK FOR PCM CHARGING SYSTEM DTCS


1. With the scan tool, read PCM DTCs.


Are there any PCM Charging System DTCs present?

Yes


No


2. CHECK SYSTEM VOLTAGE


1. Start the engine.
2. With the scan tool, under transmission, check system voltage.


Is the transmission system voltage above 9.0 volts?

Yes


No


3. CHECK THE (A1) B (+) CIRCUIT



1. Turn the ignition off to the lock position.


NOTE: Due to different power control configurations, the Transmission Control Relay may be referred to as a PCM relay.
2. Remove the Transmission Control Relay.
3. Ignition on, engine not running.
4. Using a 12-volt test light connected to ground, check the (A1) B (+) circuit in the Transmission Relay connector.

NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.


Does the test light illuminate brightly?

Yes


No


4. CHECK THE (T16) TRANSMISSION RELAY OUTPUT CIRCUIT



1. Turn the ignition off to the lock position.
2. Remove the Transmission Relay.
3. Connect a jumper wire between the (A1) B (+) circuit and the (F2) Transmission Relay Output circuit in the Transmission Relay connector.
4. Start the engine.
5. With the scan tool, under transmission, check system voltage.


Is the transmission system voltage above 9.0 volts?

Yes


No


5. CHECK THE (T16) FUSED TRANSMISSION RELAY OUTPUT CIRCUIT



1. Turn the ignition off to the lock position.
2. Disconnect the TCM C1 harness connector.
3. Ignition on, engine not running.
4. Using a 12-volt test light connected to ground, check the (T16) Fused Transmission Relay Output circuit in the TCM C1 harness connector.


NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.


Does the test light illuminate brightly?

Yes


No


6. CHECK (Z916) GROUND CIRCUIT



1. Turn the ignition off to the lock position.
2. Using a 12-volt test light connected to 12-volts, check the (Z916) Ground circuit in the TCM C1 harness connector.


Does the test light illuminate brightly?

Yes


No


7. CHECK THE WIRING AND CONNECTORS


1. The conditions necessary to set this DTC are not present at this time.
2. Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
3. Wiggle the wires while checking for shorted and open circuits.


Where there any problems found?

Yes


No