Dodge Challenger Wipers Stuck On & No Turn Signals? Full Diagnostic Breakdown
Introduction
Electrical issues can be some of the most frustrating problems to diagnose on modern vehicles—especially when multiple systems fail at once. In this case, I was dealing with a vehicle that had a check engine light, completely inoperative steering column controls, and wipers that would run continuously with no way to shut them off. This wasn’t a simple blown fuse or bad switch—it turned into a solid example of network diagnostics and module failure.
Let’s walk through the process step by step so you can see how to properly approach a problem like this.
Vehicle Concern
The vehicle came in with multiple complaints:
Check engine light on
No turn signals
No high beams
No wiper or washer function from the stalk
Wipers would run continuously when the relay was installed
At first glance, this looks like a switch issue—but as you’ll see, it goes much deeper.
Initial Inspection & Symptoms
I started with a basic function check:
Confirmed all stalk functions were dead
Installed the wiper relay and verified wipers ran nonstop
No response from any steering column inputs
This immediately told me two important things:
The system wasn’t responding to input
The wipers were being commanded on without user input
That’s a big red flag pointing toward a control module or network issue—not just a bad switch.
Diagnostic Trouble Codes
Next step was to hook up the scan tool and see what the vehicle was reporting.
Multiple modules were throwing communication-related codes, including:
Loss of communication with the steering column control module (SCCM)
Loss of steering angle sensor data
Invalid or missing data between modules
Wiper circuit faults (short to ground / open circuit)
These weren’t isolated codes—they were spread across multiple systems like the ABS, BCM, and EPS.
That tells you right away: this is a network problem.
Diagnostic Process
Step 1: Network Topology Check
I pulled up the full module list on the scan tool.
One thing stood out immediately:
👉 The steering column control module (SCCM) was completely missing from the network.
Not just throwing codes—not responding at all.
That’s a critical clue.
Step 2: Attempt Communication with SCCM
Using both an aftermarket scan tool and the factory WiTECH system, I tried to directly access the SCCM.
Result:
❌ No communication
❌ Module would not wake up
❌ Not detected on the network
At this point, we know the module is either:
Not powered
Not grounded
Or internally failed
Step 3: Power Distribution Check
Before condemning any module, you always verify power and ground.
I checked:
Underhood fuse box
Rear fuse panel
All fuses tested good—no blown circuits, no obvious issues.
This rules out a simple power supply problem.
Step 4: Wiper Relay Behavior Test
Here’s where things got interesting.
I found the wiper relay had been removed and left inside the vehicle. That’s usually a sign someone was trying to “disable” a problem.
I reinstalled the relay.
👉 Immediately, the wipers turned on and would not shut off.
That confirms:
The system is actively being commanded ON
Not just a mechanical failure
Since the stalk wasn’t working, that command had to be coming from somewhere else—most likely a module fault or corrupted input.
Step 5: Correlating Symptoms
Let’s line everything up:
No stalk inputs (turn, wipers, high beams)
SCCM missing from network
Wipers stuck on with relay installed
Multiple communication codes across modules
All of these systems rely on the SCCM to communicate driver inputs.
If that module goes down:
No signals reach the BCM
Systems default or behave erratically
Key Findings
After completing diagnostics, here’s what stood out:
SCCM completely offline
No communication with scan tools
Not visible on network topology
Power distribution verified good
Wiper system receiving incorrect command
Multiple modules reporting loss of SCCM data
This wasn’t intermittent. This was a hard failure.
Final Diagnosis / Recommendation
The steering column control module (SCCM) has failed internally.
Because the SCCM acts as the communication hub for:
Turn signals
Wipers
High beams
Steering angle data
Its failure caused:
Loss of all stalk functions
Network communication faults
Erratic wiper operation
Recommended Repair:
Replace SCCM
Perform necessary programming/configuration
Calibrate steering angle sensor after installation
Common Causes of This Issue
This type of failure isn’t extremely common, but I’ve seen it enough to recognize patterns.
Typical causes include:
Internal module failure (most common)
Voltage spikes or poor battery condition
Water intrusion (less common but possible)
Wiring stress at steering column (tilt/telescope movement)
Previous improper repairs or tampering
In this case, the removed relay strongly suggests someone previously encountered the issue and tried to work around it.
Tips for DIYers or Buyers
If you run into something similar, here are some key takeaways:
1. Don’t Assume It’s Just a Switch
When multiple functions fail at once, think module or network—not just a bad stalk.
2. Always Check Module Communication
If a module doesn’t show up on the scan tool, that’s a huge clue.
3. Verify Power Before Replacing Parts
Never skip fuse and power checks—you don’t want to replace a module that isn’t getting voltage.
4. Watch for “Workarounds”
Missing relays or unplugged components often mean someone already tried to hide a problem.
5. Use the Right Tools
A professional scan tool (especially factory-level like WiTECH) makes a big difference in diagnosing network issues.
Conclusion
This was a great example of how modern vehicle systems are interconnected. What looks like a simple wiper or turn signal issue can quickly turn into a network-level failure.
By following a structured diagnostic approach—checking communication, verifying power, and understanding system relationships—you can avoid guessing and get to the root cause efficiently.
In this case, everything pointed back to one failed component: the SCCM.
Replace it, program it, and the entire system should return to normal operation.
Call to Action
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