P0577 Cruise Control Input Circuit High
Description and meaning of DTC p0577
This is a generic powertrain diagnostic trouble code (DTC) and typically applies to OBD-II vehicles equipped with cruise control. Vehicle makes may include but aren't limited to Chevrolet (Chevy), Toyota, Ford, Harley, Dodge, Ram, Ford, etc. The ECM (Engine control module) spends most of it's time making sure your engine is working as it should all while keeping emissions, fuel economy, performance, noises, creator comfort functions at acceptable levels. Cruise control is a great feature for long trips given the fact that you do not need to control the speed of the vehicle. The ECM can take care of this as long as the cruise control system is free of any defects. If you are reading this, more than likely your cruise control has stopped working. A good sign that the cruise control has been completely disabled by the ECM is, the cruise control light on the dash doesn't come on when you try to activate it. Generally speaking, this trouble code means that the control input has suffered an electrical malfunction that stems from numerous potential causes. The P0577 Cruise Control Input Circuit High and related codes (P0575 and P0576) are set when the ECM detects a malfunction within the cruise control input circuit, in this case it means there is a high voltage condition.
p0577 diagnostic trouble code symptoms
The most common symptom out there in regards to the P0577 code, is the fact that the cruise control system itself or any of it's functions stop working. Other potential symptoms may include:CEL (check engine light) will turn on within a few drive cycles after the ECM has detected that there's an issueErratic or intermittent cruise control function(s) operationCruise control light on constant or does not come on
DTC p0577 - possible causes
Causes for this P0577 cruise control code may include:The most common cause of abnormal voltage/resistance level in the cruise control input circuit is a faulty cruise control switch that could potentially be caused by spilled liquids that short circuits the device and/or circuits within. Wiring issue (e. g. open circuit, short to ground, short to power, etc. )ECM (engine control module) issue (i. e. internal short, open, etc. )Open or shorted cruise control function switch(s)Damaged connectors within the cruise control systemBlown fuses, which could indicate a much more serious problem. (e. g. short, voltage spikes, control module(s) defective, etc. )
How to fix OBD-II diagnostic trouble code p0577
The first step in the troubleshooting process for any malfunction is to research the Technical Service Bulletins (TSB) for known issues with the specific vehicle. Advanced diagnostic steps become very vehicle specific and may require the appropriate advanced equipment and knowledge to perform accurately. We include basic steps below but refer to a vehicle year/make/model/powertrain specific repair guide for specific steps for your vehicle. Basic Step #1After recording the active P0577 code with your OBD-II DTC scanner, you should conduct an in-depth inspection of the vehicle's connectors, wirings, and other parts of the cruise control system. It is also important that any damaged connectors (e. g. broken tabs, heat damage, corroded, etc. ) be replaced, reconnected, or repaired as necessary. You will need to clear the code and perform a sort test drive, try using the cruise control functions now. If everything is working after the repair, you should ensure that the CEL (Check engine light) no longer reappears. Otherwise, if it does light up again and the code has been stored in the ECM once more, continue your diagnostics. Basic Step #2Test the cruise control switch (AKA: Multifunction switch). Refer to your make and model's service manual to acquire the correct desired values and diagnostic procedures specific to your vehicle. Most times, this will involve using your DVOM (or multimeter) to record the electrical values present. After comparing your actual values to the manufacturer's desired ones, you will be able to pinpoint the switch as the issue or rule out as a possibility. Basic Step #3If the switch has been found to be defective, replacing it may not be an easy task, given the fact that there may be airbags in the way of replacing it. That said, it could be as simple as removing 1 or 2 steering column covers to access the switch. If you've pinpointed it as your problem, found it to be defective and replaced it following the specific steps unique to your vehicle, test drive the vehicle after clearing the active codes. This article is strictly for information purposes only and the technical data and service bulletins for your specific vehicle should always take precedence.