U0168 code meaning
Lost Communication With Vehicle Security Control Module
Network system Generic code U01xx codes Check engine light
What U0168 means
U0168 points to the vehicle security control module, which handles anti-theft and key authorisation and in many layouts also hosts the immobilizer handshake. Chrysler shows the link: its 2011 field report names U0168 for the SKREEM/WCM, and bulletin 18-023-13 (Grand Voyager 2.8 L diesel 2012-2013) treats it as a sign of a failed ignition handshake that new PCM software fixes. Jeep TSB 08-088-25 (Grand Cherokee 4xe 2024) lists it with MIL and a no-start. Mercedes stores U0168 in the 48 V starter-alternator of the 2021 S 580 for the electronic ignition lock; the MIL clears after three drive cycles. GM's Saab list calls it the keyless entry module. U0167 is the immobilizer module, U0427 invalid security data.
U0168 at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyHard
- Typical labor0.3 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0168
- No start or delayed start
- Check engine light on (Jeep 4xe, Mercedes S 580)
- Keyless entry, alarm or key detection not working
Common causes of U0168
- Most likelyEngine or security module software mishandles the key handshake (Chrysler, Jeep, Mercedes updates)
- PossibleSecurity module without power or ground
- PossibleBus line or connector to the security module faulty
- Less likelySecurity or keyless entry module faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Vehicle security moduleCAN bus wiring
What each part of U0168 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 68 | The exact fault in that area. |
What to do next
- Note U0168 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 U0168
What does U0168 mean?
U0168 means "Lost Communication With Vehicle Security Control Module". U0168 points to the vehicle security control module, which handles anti-theft and key authorisation and in many layouts also hosts the immobilizer handshake. It is a generic code, so it means the same on every make.
Is it safe to drive with U0168?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will U0168 fail an emissions test?
U0168 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 U0168 to fix?
Difficulty: hard. A typical repair takes 0.3 to 4 hours of work. This is a job for a workshop.
Will U0168 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.