Transfer Case Control System MIL Request
The P0800 code means the vehicle's onboard diagnostic system has detected: Transfer Case Control System MIL Request. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- hard
- Estimated cost
- $150 - $1,200 (parts and labor)
Read and clear transmission codes. Many trans codes are caused by low or burnt fluid -- check level and color before assuming the worst.
Basic scanners only read engine codes. This reads transmission, ABS, and airbag too.
Affiliate links — we earn a commission at no extra cost to you.
What Are the Symptoms of P0800?
- Check Engine Light illuminated
- Transfer case warning light on
- Difficulty shifting between 2WD and 4WD
- Unusual noises from the transfer case
What Causes P0800? (Most Likely First)
- Transfer case control module malfunction Very High
- Faulty transfer case motor or encoder High
- Wiring or connector issue in transfer case circuit Moderate
- Low or contaminated transfer case fluid Low
Can I Still Drive with P0800?
Short distances only. P0800 is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
Can I still drive my vehicle with P0800?
You can drive short distances, but the transfer case may not shift properly. Avoid off-road or slippery conditions until the issue is resolved.
Is P0800 expensive to fix?
It depends on the root cause. A wiring fix or fluid change is inexpensive, but a faulty transfer case motor or control module can cost $500 to $1,200.
Does P0800 only appear on 4WD vehicles?
Yes, P0800 is specific to vehicles with a transfer case, which includes 4WD and AWD vehicles.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose P0800?
-
Scan for additional transfer case DTCs to pinpoint the specific fault
-
Inspect the transfer case control module connector for corrosion or damage
-
Check transfer case fluid level and condition
-
Test the transfer case motor and encoder ring with a scan tool
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
Which Vehicles Commonly Get P0800?
- 2007-2018 Jeep Wrangler
- 2005-2019 Ford F-150 4WD
- 2007-2017 Chevrolet Silverado 4WD
- 2005-2015 Toyota Tacoma 4WD
Explore More
Was this helpful?
Send this to whoever is fixing the car — your mechanic, or the person asking what the light means.