U0158 Lost Communication With Head-Up Display: Meaning, Causes, Symptoms & Fix

U0158 Lost Communication With Head-Up Display means another vehicle control module can no longer exchange messages with the head-up display module over the communication network. The most common causes are a blown fuse, low system voltage, a failed HUD unit, damaged wiring, poor ground, or a CAN-bus fault. Do not replace the display immediately: a network problem elsewhere in the vehicle can create the same code.

This is primarily an information and diagnosis issue, but it can become a safety concern if the HUD is the only source of speed, navigation, warning, or driver-assistance information. The correct repair starts with checking power, ground, network voltage, and related fault codes in a logical order.

What Does the U0158 Code Mean?

U0158 is a generic OBD-II network code defined as Lost Communication With Head-Up Display. The code is set when a control module, often the body control module, gateway, instrument cluster, or advanced driver-assistance controller, fails to receive expected messages from the HUD module for a calibrated period.

The HUD normally receives vehicle data through the CAN network, including road speed, engine information, navigation instructions, warning messages, and sometimes lane or collision alerts. U0158 does not automatically prove that the projector or display screen has failed. It only confirms that communication with the module has been interrupted.

Common Symptoms of U0158

Some vehicles store U0158 without showing an obvious dashboard symptom, especially when the fault was caused by a brief voltage drop. In other cases, the driver may notice several network-related problems at the same time.

• The head-up display is blank, flickers, or shuts down intermittently.
• Projected speed, navigation, or warning information is missing.
• The instrument cluster displays a communication or service message.
• Several unrelated warning lights appear after a weak-battery event.
• Other modules report U-codes, such as U0001, U0156, or gateway communication faults.
• The code returns immediately after being cleared.

A useful diagnostic clue is whether the HUD fails only during engine cranking, after rain, over bumps, or when accessories are switched on. Those patterns often point to low voltage, moisture intrusion, a loose connector, or a marginal ground rather than a defective display.

Most Likely Causes of U0158

• Low battery voltage: A weak battery or poor charging system can make several modules reset during startup.
• Blown fuse or power supply problem: The HUD may have a separate fuse, ignition feed, or wake-up circuit.
• Bad ground: A loose body ground or corroded ground eyelet can interrupt communication even when battery voltage looks normal.
• Open or shorted CAN wiring: CAN High and CAN Low wires can be damaged by previous repairs, water, vibration, or aftermarket equipment.
• Connector corrosion: A small amount of moisture in a low-current network connector can create an intermittent fault.
• Failed HUD module: Internal electronics may fail after heat exposure, liquid damage, or an electrical surge.
• Gateway or software issue: A network gateway may stop routing messages, or a module may require a software update or configuration procedure.

How to Diagnose U0158 Correctly

A basic code reader may display U0158 but cannot identify which module stopped communicating. A professional scan tool that can access every control module is much more useful because it shows whether the HUD is offline and which other modules have lost contact with it.

1. Record all codes before clearing anything

Scan the entire vehicle, not only the engine computer. Note whether the codes are current, stored, or history faults. If many modules report communication failures at the same time, suspect a shared power, ground, gateway, or CAN-bus problem before condemning the HUD.

2. Check battery and charging voltage

With the vehicle switched off, a healthy fully charged battery is typically near 12.6 volts. During cranking, voltage should not collapse excessively, and with the engine running the charging voltage commonly falls in the approximate 13.5–14.8-volt range, depending on the vehicle. Always compare the readings with the manufacturer’s specifications.

3. Verify HUD fuses, power, and ground

Test both sides of each relevant fuse with the circuit switched on; a visual inspection can miss a fuse that fails under load. At the HUD connector, confirm battery or ignition power and perform a voltage-drop test on the ground circuit. A ground that appears intact with a test lamp can still fail when the module draws current.

4. Inspect the CAN network

Look for crushed wiring, aftermarket alarm or audio splices, water in connectors, and terminals pushed backward inside the plug. With the vehicle powered down and the network asleep, many properly terminated CAN systems measure close to 60 ohms across CAN High and CAN Low. A reading near 120 ohms may indicate one missing termination, while a very low reading suggests a short; exact testing conditions vary by vehicle, so use the service manual before interpreting the result.

5. Check for a module or gateway failure

If power, ground, wiring, and network resistance are correct but the HUD remains absent from the scan tool, the module may have failed or lost its configuration. Replacement can require programming, calibration, or vehicle-specific initialization. On vehicles with a motorized or adjustable display, a mechanical obstruction can also prevent normal operation without being the original network cause.

How to Fix U0158

1. Charge or replace a weak battery and repair any charging-system fault.
2. Replace the correct fuse only after confirming there is no short circuit.
3. Clean and tighten affected grounds using the manufacturer’s corrosion-repair procedure.
4. Repair damaged CAN wiring with the correct twisted-pair routing, wire size, and splice method.
5. Dry, clean, or replace corroded connectors and correct any water leak.
6. Update, configure, or replace the HUD module when testing proves it is not communicating.
7. Clear the codes, cycle the ignition, perform a road test, and rescan every module.

Avoid installing a used HUD module without checking compatibility. Many modern displays are coded to the vehicle and may require immobilizer-related configuration, calibration, or a security-access procedure. The repair is not complete until the module communicates normally and the code stays cleared after several ignition cycles.

Can U0158 Be Related to U0001?

Yes. U0001 means a fault involving the high-speed CAN communication bus. If U0001 and U0158 appear together, the HUD may be only one victim of a wider bus problem. A shorted module, damaged CAN pair, failed termination, power supply issue, or gateway fault can prevent multiple modules from communicating.

To fix a high-speed CAN bus fault, first identify whether the bus is completely offline or whether only one module is missing. Disconnecting suspected modules one at a time, while monitoring network recovery with a scope or scan tool, can isolate a module that is pulling the bus down. Do not randomly unplug safety-critical modules or bridge CAN wires; follow the wiring diagram and manufacturer test sequence.

What Does U0156 Mean?

U0156 generally means Lost Communication With Information Center A. The exact naming can vary slightly by manufacturer, but it usually refers to an information display or center module rather than the head-up display. U0156 and U0158 can appear together when they share a power feed, gateway, connector, or CAN network segment.

The distinction matters because replacing a HUD for a U0156 fault, or replacing an information-center module for U0158, may solve nothing. Always verify the vehicle-specific code definition and identify which module is actually offline.

What Does U0158 Mean on a Harley-Davidson?

On a Harley-Davidson, interpretation requires extra caution. Most Harley-Davidson motorcycles do not use a factory automotive-style head-up display, so a generic scanner may display a code description that does not match the motorcycle’s installed equipment. The code could be a translation error, a non-factory accessory issue, a communication fault in a related display or infotainment system, or a code that is not supported by the motorcycle’s diagnostic software.

Use a Harley-capable diagnostic tool and the service information for the exact model year. Check the battery, main grounds, accessory wiring, connectors, and CAN lines before assuming a HUD module exists or needs replacement. This is especially important after installing an aftermarket infotainment unit, navigation system, lighting controller, or alarm.

Is It Safe to Drive With U0158?

If the HUD is the only failed feature and the conventional instrument cluster, speedometer, warning lamps, and other safety systems work normally, a short trip to a repair facility may be reasonable. Do not continue driving if the vehicle has no reliable speed display, multiple active communication faults, ABS or stability-control warnings, steering problems, or intermittent engine shutdown.

Repair costs vary widely. A battery or fuse may cost relatively little, while CAN wiring diagnosis, gateway replacement, or a programmed HUD module can be substantially more expensive. The diagnostic time is often the largest variable because intermittent network faults must be reproduced and isolated rather than guessed at.

Final Takeaway

U0158 identifies a communication failure with the head-up display, not a guaranteed HUD hardware failure. Start with a full-module scan, battery and charging tests, fuses, grounds, connector condition, and CAN-bus checks. If U0001 or U0156 is also present, investigate the shared network before replacing any display. A vehicle-specific wiring diagram and a scan tool with manufacturer-level access are the safest route to a lasting repair.

Frequently Asked Questions

Can a weak battery cause U0158?

Yes. Low voltage during starting can reset the HUD or gateway and store a lost-communication code. Test the battery under load and verify charging voltage before replacing modules.

Will clearing U0158 fix the problem?

It may remove a history code caused by a temporary voltage drop, but it will not repair an active wiring, power, or module fault. Rescan after cycling the ignition and driving the vehicle.

How do I fix a high-speed CAN communication bus fault?

Check shared power and grounds, inspect CAN wiring and connectors, measure the network correctly, and isolate a module that is shorting the bus. Use the manufacturer’s wiring diagram rather than applying a generic resistance test blindly.

Is U0158 the same as U0156?

No. U0158 concerns communication with the head-up display, while U0156 generally concerns Information Center A. They can share a network or power fault, but they identify different modules.

What should I do if U0158 appears on a Harley-Davidson?

Confirm the code with a Harley-capable scan tool and verify the exact model’s equipment. Since many Harley-Davidson motorcycles do not have a factory HUD, check for a scanner translation issue or an aftermarket display and communication problem.