DTC P0560 System Voltage. Pontiac Firebird 1999

For 1990-2009 cars only

Makes 🢒 Pontiac 🢒 1999 🢒 Firebird 🢒 Engine 🢒 Engine Controls - 3.8L 🢒 DTC P0560 System Voltage

Engine Controls Components
Gen Control, IAC , Check Gauges Lamp
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The PCM monitors system voltage on the PCM ignition feed circuit. If the system voltage is out of tolerance, DTC P0560 will be set. When the conditions that set DTC P0560 are present, operation of some vehicle systems and components may be affected.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

•	System voltage monitored at the PCM ignition feed circuit is less than 10 volts or greater than 16 volts.

•	Above conditions must be present for longer than 25 seconds.

Action Taken When the DTC Sets

•	The PCM will not illuminate the malfunction indicator lamp (MIL).

•	The PCM will store conditions which were present when the DTC set as Failure Records data only. This information will not be stored as Freeze Frame data.

Conditions for Clearing the MIL/DTC

•	A History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.

•	The DTC can be cleared by using the scan tool Clear Info function.

Diagnostic Aids

Check for the following conditions:

Important:: Be sure to inspect PCM engine grounds for being secure and clean.

•	Poor connection at PCM - Inspect harness connectors for the following items:

-	Backed out terminals

-	Improper mating

-	Broken locks

-	Improperly formed or damaged terminals

-	Poor terminal to wire connections

•	Damaged harness - Inspect the wiring harness for damage.

•	If the harness appears to be OK, observe the Ignition 1 voltage display on the scan tool while moving connectors and wiring related to the PCM, dash harness, and engine harness. A change in the display will indicate the location of the fault.

Important: Charging with a battery charger while starting the engine can cause DTC P0560 to be set.

If DTC P0560 cannot be duplicated, review the Freeze Frame/Fail Records vehicle mileage since the diagnostic test last failed. This may help determine how often the condition that caused the DTC to be set occurs. For complete information and additional diagnostics for the vehicle charging system, refer to Charging System .

Test Description

Number(s) below refer to the step number(s) on the Diagnostic Table.

This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is replaced, the new PCM must be programmed.

DTC P0560 - System Voltage

Step	Action	Value(s)	Yes	No
1	Did you perform the Powertrain On-Board Diagnostic System Check performed?	--	Go to Step 2	Go to Powertrain On Board Diagnostic (OBD) System Check
2	Is DTC P1635 also set?	--	Go to DTC P1635 5 Volt Reference Circuit	Go to Step 3
3	Start and run engine above 1000 RPM. With a scan tool, observe the Ignition 1 voltage parameter. Does the scan tool indicate voltage within the specified range?	10-16V	Go to Step 4	Go to Step 5
4	Turn ON the ignition, with the engine OFF. With a scan tool, review and record Fail Records. Operate vehicle within Fail Records conditions. Does the scan tool indicate this DTC failed this ignition?	--	Go to Step 5	Go to Diagnostic Aids
5	Connect a J 39200 Digital Multimeter between the battery terminals. Observe the voltage while running the engine above 1000 RPM. Does the voltage measure within the specified range?	10-16V	Go to Step 6	Go to Step 7
6	Load the electrical system by turning ON the headlamps and the HVAC high blower. Observe the DMM voltage while running the engine above 2000 RPM. Does the voltage measure within the specified range?	10-16V	Go to Step 8	Go to Step 7
7	Turn OFF the ignition. Disconnect the generator. Measure the voltage on the generator control circuit using a DMM that is connected to a good ground. Start the engine. With a scan tool, command the Gen. L Term. ON. Does the voltage measure near the specified value with the Gen. L Term. commanded ON?	5V	Go to Step 12	Go to Step 10
8	Compare the Ignition 1 voltage parameter on the scan tool with the actual battery voltage read with the DMM. Do the voltages match?	--	Go to Diagnostic Aids	Go to Step 9
9	Inspect the PCM ignition feed circuit for a poor connection between the ignition switch and the PCM. Refer to Intermittents and Poor Connections Diagnosis and Connector Repairs . Did you find and correct the condition?	--	Go to Step 14	Go to Step 13
10	Test the generator control circuit for an open or a short to ground. Refer to Wiring Repairs . Did you find and correct the condition?	--	Go to Step 14	Go to Step 11
11	Inspect the generator control circuit for a poor connection at the PCM. Refer to Intermittents and Poor Connections Diagnosis and Connector Repairs . Did you find and correct the condition?	--	Go to Step 14	Go to Step 13
12	Inspect the generator control circuit for a poor connection at the generator. Refer to Intermittents and Poor Connections Diagnosis and Connector Repairs . Did you find and correct the condition?	--	Go to Step 14	Go to Generator Assembly Check
13	Important:: The replacement PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming . Replace the PCM. Did you complete the replacement?	--	Go to Step 14	--
14	Start and run the engine above 1000 RPM. With a scan tool, observe Ignition 1 voltage parameter. Does the scan tool indicate voltage within the specified range?	10-16V	System OK	Go to Step 5