Damaged or corroded wiring in the TCS PWM circuit, especially at connectors or where the harness flexes; Failed TCS pump motor or valve solenoid that cannot generate the expected feedback signal; Faulty TCS/ABS control module not outputting or interpreting the PWM signal correctly; Blown fuse or poor ground connection supplying power to the TCS hydraulic unit; Water intrusion or contamination in the TCS pump connector causing intermittent signal loss; Internal short or open in the TCS pump motor winding

DTC codes / Chrysler codes / P1571

P1571 · ChryslerTCS PWM Circuit No Frequency

Q: What does code P1571 mean?

TCS PWM Circuit No Frequency. P1571 on Chrysler vehicles means the Traction Control System (TCS) module has detected no frequency signal on the pulse-width modulated (PWM) circuit that controls the traction control valve or pump. The computer expects a rapidly switching electrical signal to operate the TCS hydraulic components, but it sees a flat or missing signal instead.

P1571 on Chrysler vehicles means the Traction Control System (TCS) module has detected no frequency signal on the pulse-width modulated (PWM) circuit that controls the traction control valve or pump. The computer expects a rapidly switching electrical signal to operate the TCS hydraulic components, but it sees a flat or missing signal instead.

SystemPowertrain

Code typeChrysler specific

SeverityMedium

Fix difficultyIntermediate

AreaVehicle speed, idle control and auxiliary inputs

Symptoms you may notice

Traction control warning light illuminated on the dashboard
Anti-lock brake system (ABS) light may also be on if the TCS shares the ABS module
Traction control system disabled, allowing wheel spin on slippery surfaces
Often no symptoms besides the warning light, with normal braking and driving feel
In some cases, a slight pulsation or unusual noise from the ABS/TCS hydraulic unit when the system attempts to activate

Common causes, most likely first

Damaged or corroded wiring in the TCS PWM circuit, especially at connectors or where the harness flexes
Failed TCS pump motor or valve solenoid that cannot generate the expected feedback signal
Faulty TCS/ABS control module not outputting or interpreting the PWM signal correctly
Blown fuse or poor ground connection supplying power to the TCS hydraulic unit
Water intrusion or contamination in the TCS pump connector causing intermittent signal loss
Internal short or open in the TCS pump motor winding

How to diagnose and fix it

Connect a scan tool and read all ABS/TCS codes to confirm P1571 is the only or primary fault
Inspect the TCS pump connector and wiring for corrosion, chafing, or loose pins; clean and repair as needed
Check the fuse and ground for the TCS hydraulic unit with a multimeter and test light
Back-probe the PWM circuit at the TCS module and at the pump to verify signal presence with an oscilloscope or duty-cycle meter
Command the TCS pump on with the scan tool and listen for operation; if no sound, test the pump motor directly with fused power
If the pump motor runs but no signal is seen, check the module's output; substitute a known-good module only after all wiring checks pass
Clear codes and perform a road test to verify the repair and ensure the TCS light stays off

What most techs overlook on P1571

A weak or failing battery can cause the TCS module to log P1571 because low voltage disrupts the PWM signal generation, so always load-test the battery before condemning the pump.
The TCS PWM circuit often shares a connector with the ABS wheel speed sensors; a single corroded pin there can set P1571 without any ABS codes, leading to misdiagnosis of the pump.
Aftermarket brake pads or rotors with excessive runout can trigger the TCS to activate momentarily and set a frequency code if the system sees unexpected wheel speed differences, so check mechanical brake condition first.
On some Chrysler models, the TCS pump motor is serviceable separately from the valve body, but the motor must be indexed correctly during installation or the PWM signal will be erratic.
A scan tool that can graph PWM duty cycle is far more useful than a basic code reader here; many parts are replaced because the signal was never actually measured.

Can I keep driving with P1571?

You can usually continue driving with the warning light on because normal braking remains unaffected, but avoid relying on traction control in wet or slippery conditions and do not tow or drive aggressively until the fault is repaired.

Tools that help

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Guidance is general and written for Chrysler vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.