U0404: Invalid Data Received From Gear Shift Control Module A
A generic network and communication trouble code, same meaning on every brand.
Only with a working handbrake habit - if the shifter is electronic, this fault can mean Park does not engage when you believe it did. Always set the parking brake, and if the selector stops responding at all, do not drive.
Symptoms
- Gear indicator wrong or flashing
- Shifter commands ignored or delayed
- Warnings about shifting to Park
- Car restrained only by the parking brake in worst cases
Likely causes, most common first
- Shift-by-wire module sending implausible data
- Selector position sensor fault
- Low system voltage corrupting messages
- CAN wiring fault on the shifter branch
Read U0404 yourself before paying for diagnosis
A basic Bluetooth OBD-II scanner ($20-40) plugs into the port under the dashboard and shows this code with live sensor data on your phone - useful both for confirming the fix and for talking to a shop from an informed position.
What is going on and how it gets diagnosed
U0404 means other computers received data from the gear shift control module that failed their sanity checks. On cars with a mechanical linkage this is mostly an indicator nuisance; on shift-by-wire cars - rotary dials, toggle shifters, column stalks with no cable - the shifter IS this module, and implausible data from it deserves full attention, because Park on such cars is a request, not a mechanical fact.
The safety habit costs one second: parking brake, every stop, until repaired - rollaway incidents on shift-by-wire designs are documented enough to have driven recalls across several brands. Diagnostically, weak system voltage is the quiet classic (shifter modules complain first when a battery sags), followed by the selector's own position sensors and its network branch. A shop with a scan tool sees which specific messages were rejected, which shortcuts the guessing considerably.
Repair options and cost
Typical US independent-shop ranges, parts and labor. Dealers run higher; regional labor rates vary.
Owner reports mentioning U0404
“While accelerating the vehicle lost power and the prndl lights all illuminated. After a few seconds power resumed. This has happened several times and the check engine light has come on. We have been told its error code u0404 and the electronic shift module needs to be replaced. It appears this is a very common occurrence for this year vehicle. It is a safety concern because if it happened during high traffic times it could certainly cause an accident. *tr”2007 Jeep Grand Cherokee · Sep 2014 · 80,200 mi
“The check engine light comes on. Had the code checked (u0404). Invalid data received from gear shift module. Took jeep to dealer and they checked code ( it was stored ). They would not work on the jeep because the code was not active. The check engine light with this code has come on a lot of times. I am concerned about the jeep stalling while driving.”2007 Jeep Grand Cherokee · Jul 2014 · 42,000 mi
“The dashboard lights came on all at once. Than was fine continued driving and check engine light came on and tried to make it home. However never made it p,r,n,d all lit up and started loosing power. Was able to make it to side of road. Check engine light code was u0404 and now the gear shift control module needs to be replaced. However after looking over other complaints from jeep owners I see this has been a problem on these vehicles. I think its time for a recall especially that it happens every 30,000 -40,000 miles. Unreal at the cost of repair. Nothing like a scam. Will never own a jeep again.. *tr”2007 Jeep Grand Cherokee · Jun 2012 · 88,000 mi
Show 1 more owner reports
“Vehicle lost power (engine rpm went to idle) for no apparent reason while turning onto a multi-lane hwy and accelerating. Power was restored and vehicle accelerated normally. Vehicle "check engine" light illuminated. This has continued to occur several times in the last month. "check engine" code u0404 was verified through jeep is the "tcm" transmission control module.”2007 Jeep Grand Cherokee · Dec 2010 · 38,000 mi
Cars that report U0404 most often
Based on mentions of this code in NHTSA owner complaints.
Frequently asked questions
Can I drive with U0404?
Only with a working handbrake habit - if the shifter is electronic, this fault can mean Park does not engage when you believe it did. Always set the parking brake, and if the selector stops responding at all, do not drive.
How much does it cost to fix U0404?
Typical US repair costs range from $0 for the simplest fix (battery and ground service) to $1,000 in the worst case. The right number depends on which cause your car has - see the causes list.
Related codes
The codes closest to U0404. They often appear together, and telling them apart is usually what narrows the diagnosis.
Definition per SAE J2012 standard nomenclature. Symptoms, causes and costs are editorial guidance - always confirm with a diagnosis of your specific vehicle.