U3008 code meaning
Control Module Ground A
Network system Generic code U30xx codes Check engine light
What U3008 means
Modules that switch large currents are often grounded through two separate wires, and U3008 marks the loss of ground A. GM's 19OBDG03B brake module measures the voltage on both grounds and forms (G1 − G2)/(G1 + G2); each wire should carry half the current, so a result above 0.9 for 200 ms means ground 1 is gone, Type A with MIL. Ford's TSB 26-2150 for 2025–2026 Explorer, Police Interceptor and Aviator ties U3008:1B in the steering module, the byte meaning resistance too high, to ground G104 or G116 on the passenger frame rail; the repair enlarges the hole and fits a self-tapping M8 bolt. On the road this shows as a steering assist warning and heavier steering. Mazda uses U3008:01 on CX-90 and CX-70 plug-in hybrids for an over-current or voltage fault in the backup power unit instead.
U3008 at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U3008
- Steering assist or brake system warning in the cluster
- Reduced power steering assist or limited ABS function
- Check engine light where the maker classes it as MIL-relevant
Common causes of U3008
- Most likelyLoose or poorly clamped ground eyelet at the body or frame
- PossibleCorrosion or paint under the ground connection raising resistance
- Less likelyBroken or chafed ground wire A in the harness
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Module ground aGround strap
What each part of U3008 means
| U | Network system: communication between the control modules (CAN bus). |
| 3 | Reserved range, usually generic. |
| 08 | The exact fault in that area. |
What to do next
- Note U3008 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about U3008
What does U3008 mean?
U3008 means "Control Module Ground A". Modules that switch large currents are often grounded through two separate wires, and U3008 marks the loss of ground A. It is a generic code, so it means the same on every make.
Is it safe to drive with U3008?
Drive gently and only to a workshop. With U3008 the car can go into limp mode (reduced power) to protect itself.
Will U3008 fail an emissions test?
U3008 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is U3008 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will U3008 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.