P0561

DTC P0561

Circuit Description

The transmission control module (TCM) requires a switched ignition voltage input and a direct battery voltage input.


DTC P0561 is a type C DTC.


DTC Descriptor

This diagnostic procedure supports the following DTC:


DTC P0561 System Voltage Unstable


Conditions for Running the DTC

* The components are powered and ignition voltage is greater than 9.0 volts and less than 18 volts.
* Engine speed is greater than 400 RPM for 0.5 second.



Conditions for Setting the DTC

DTC P0561 sets when the TCM detects a large variation in ignition voltage or battery direct voltage. When an ignition or battery direct voltage variation of 4.0 volts or greater is detected for 0.5 second, a fault pending is reported. After 1.0 second of 4.0 volts or greater variation, a DTC is set with a failure response.


Action Taken When the DTC Sets

* The TCM does not illuminate the malfunction indicator lamp (MIL).
* The transmission fails to hydraulic default.
* DTC P0561 is stored in TCM history.
* The TCM inhibits torque converter clutch (TCC) engagement.
* The TCM freezes shift adapts.



Conditions for Clearing the DTC

A scan tool can clear the code from TCM history. The TCM automatically clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without failure.


Diagnostic Aids

* Inspect for aftermarket devices that could affect the operation of the starting and charging systems.
* Inspect the wiring for poor electrical connections at the TCM. Inspect for the following conditions:

- A bent terminal
- A backed-out terminal
- A damaged terminal
- Poor terminal tension
- A chafed wire
- A broken wire inside the insulation

* When diagnosing for an intermittent short or open, massage the wiring harness while watching the test equipment for a change.
* You may have to drive the vehicle in order to experience a condition.
* Inspect for the presence of aftermarket accessories, such as a remote starter, etc. Depending on how these aftermarket accessories are installed, they may interfere with the required voltage for proper operation of the transmission.



Test Description

The numbers below refer to the step numbers on the diagnostic table.
3. This step observes battery feed.
4. This step observes ignition feed.
7. This step observes accessories for voltage fluctuations.