Shift Solenoid A Control Circuit High
The P0974 code means the vehicle's onboard diagnostic system has detected: Shift Solenoid A Control Circuit High. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- hard
- Estimated cost
- $150 - $800 (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.
Check Price on AmazonAffiliate link -- we earn a commission at no extra cost to you.
Basic scanners only read engine codes. This reads transmission, ABS, and airbag too.
Check Price on AmazonAffiliate link -- we earn a commission at no extra cost to you.
Common Symptoms
- Check Engine Light illuminated
- Transmission stuck in gear or limp mode
- Shift solenoid A always energized or never energized
- Abnormal shift patterns
Probable Causes (Ranked by Likelihood)
- Open ground in shift solenoid A circuit Very High
- Faulty shift solenoid A with high resistance High
- Short to battery voltage in solenoid control wire Moderate
- TCM reference voltage problem Low
Step-by-Step Diagnostic Procedure
-
Measure voltage at solenoid A connector with key on
-
Check for an open ground at the solenoid
-
Test for short to battery voltage on the control wire
-
Measure solenoid A resistance and compare to specifications
Frequently Asked Questions
Is P0974 the opposite of P0973?
Yes. P0973 indicates the solenoid circuit is stuck low while P0974 indicates it is stuck high. They are complementary electrical fault codes.
Can a solenoid with high resistance still function?
A solenoid with elevated resistance will draw less current and may not fully open or close. This can cause partial shifts, slipping, or the solenoid may not respond at all.
Do I need to drop the transmission pan to access the solenoid?
Yes, in most cases the transmission pan must be removed to access the valve body where shift solenoid A is located.
Sources
This page is built from documented references. Verify against your own service info before repair work.
P0974 on Diesel, EV & Equipment
The same code ID appears across other engines and platforms. The diagnostic flow varies by manufacturer — these are the platform-specific breakdowns:
Explore More
Was this helpful?
Share carcodefinder.com with a friend who needs to decode their check engine light.