2017 Chevy Traverse Check Engine Light and Power Window Failure – Step-by-Step Diagnosis
Introduction
Every once in a while, you get a vehicle that comes in with multiple issues that seem unrelated—but if you slow down and diagnose it correctly, you realize they’re actually separate problems stacked on top of each other. That’s exactly what happened with this 2017 Chevrolet Traverse.
This one came in with a check engine light, power windows not working correctly, and a rear wiper issue. At first glance, it might look like a simple electrical problem or even a bad module. But if you’ve been diagnosing car problems long enough, you know better than to assume.
In this case, we had to break it down step-by-step, isolate each symptom, and avoid the trap of throwing parts at it. That’s the key to proper automotive troubleshooting—and it’s what saves time, money, and comebacks.
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Power Probe ECT3000 Short Finder
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Vehicle Overview
We’re working on a 2017 Chevrolet Traverse, a mid-size SUV known for being reliable, but like any modern vehicle, it relies heavily on electronics and module communication.
Vehicle Concern
The vehicle came in with multiple symptoms:
Check engine light on
Rough idle condition
All power windows would go down from individual switches
None of the windows would go up from their individual switches
All windows worked normally from the driver’s master switch
Rear wiper arm was out of position
Anytime you see multiple electrical symptoms like this, you need to determine whether they’re connected or separate issues.
Initial Inspection
The first thing I always do is a quick visual and basic electrical check. Right away, one thing stood out—the battery voltage was low.
Testing confirmed the battery was weak, only producing around 390 cold cranking amps. That’s a problem. Low voltage can cause all kinds of strange behavior, especially on newer vehicles.
We also corrected the rear wiper arm issue by repositioning it so it no longer contacted the tailgate. That was a simple mechanical fix and unrelated to the other concerns.
Codes
A full system scan revealed multiple codes across different modules:
P0496 – EVAP system flow during non-purge condition
B1517 – Low voltage
B1516 – Battery current sensor issue
B1440 – Power mode master input circuits correlation
There were also TPMS-related codes, but those were not relevant to the main concerns.
This is where experience matters. You have to separate real faults from “noise” caused by low voltage.
Diagnostic Process
Step 1: Address the Voltage Issue
Before diving into deeper automotive troubleshooting, you always fix the foundation. A weak battery can create false symptoms and misleading codes.
The battery failed testing, so replacement was recommended right away.
Step 2: Evaluate the Check Engine Light
The P0496 code is a very common one on GM vehicles. It indicates that the EVAP system is allowing vapor flow when it shouldn’t be.
In real-world terms, that usually means a purge valve stuck open.
The rough idle backed that up. When a purge valve is stuck open, it creates a vacuum leak effect, which can cause unstable idle and fuel trim issues.
A quick functional check confirmed the diagnosis—this wasn’t a voltage-related code. It was a real mechanical failure.
Step 3: Diagnose the Window Issue
Now for the tricky part.
At first, it looked like a relearn issue due to low voltage. That’s common. When battery voltage drops, window modules can lose their position memory and disable the “up” function.
But after attempting a relearn, nothing changed.
Here’s what made this case interesting:
All windows went down from their own switches
None would go up from their own switches
All windows worked perfectly from the master switch
That pattern tells you a lot.
If it were a motor or regulator issue, it would affect individual windows—not all three. If it were wiring, you wouldn’t see consistent behavior across all doors.
So now you’re thinking control logic.
Step 4: Understanding the System
On this vehicle, the driver master switch isn’t just a switch—it acts as the central control for window commands.
Passenger switches send signals through the system, and the master switch interprets and passes those commands along.
If the master switch fails internally, it can block certain commands—especially the “up” function, which is tied to safety features like anti-pinch.
Step 5: Confirming the Fault
At this point, we ruled out:
Window motors
Regulators
Individual door switches
Wiring issues
The consistent failure across all passenger windows pointed directly to the driver master window switch.
Key Findings
Battery tested weak and caused multiple false or history codes
P0496 was an active fault caused by a failing purge valve
Window issue was not a relearn problem
Driver master switch was not passing “up” commands from other switches
Final Diagnosis
This vehicle had multiple separate issues, not one root cause:
Failed battery causing voltage-related codes and instability
Faulty EVAP purge valve causing check engine light and rough idle
Defective driver master window switch preventing proper window operation
Misaligned rear wiper arm causing mechanical interference
Each issue required its own diagnosis and repair.
Common Causes
From a broader perspective, these are common causes you’ll see in similar situations:
Weak or failing battery causing erratic electrical behavior
Stuck-open purge valves on GM vehicles triggering P0496
Master window switch failures affecting multiple windows
Misinterpreting multiple symptoms as one problem
This is why proper diagnosing car problems matters—you can’t assume everything is connected.
Lessons for Buyers / DIYers
If you’re working on your own vehicle or looking at used car inspection tips, here’s what you should take away from this case:
Don’t assume multiple symptoms have one cause. That’s one of the most common mistakes I see.
Always check battery condition first. Low voltage can create misleading symptoms and waste your time.
Understand system design. Knowing how the window system works helped narrow this down quickly.
And finally, don’t skip proper testing. Guessing leads to unnecessary parts replacement.
Don’t Get Burned on Your Next Used Car
If you’re thinking about buying a used car—or even if you already have one—this is exactly the kind of problem that can slip through the cracks and cost you big money later.
After 35+ years in the automotive field, I’ve seen firsthand how often people end up with vehicles that have hidden issues just like this.
That’s why I put together a simple Used Car Guide to help you understand what to look for and how to avoid making a costly mistake.
It’s a quick, practical guide designed to give you the right mindset and approach before you buy.
👉 https://stan.store/BobbyWhiteside
Affiliate Disclaimer
Disclaimer: Some links in this post may be affiliate links. I may earn a small commission at no extra cost to you. I only recommend tools I personally use and trust in real-world diagnostics.
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