U1170 — SCP (J1850) Invalid or Missing Data for Cellular Phone / Paging System #

Please note: The description of Diagnostic Trouble Code (DTC) U1170 may vary depending on the vehicle manufacturer. Always refer to the OEM (Original Equipment Manufacturer) service information for your specific model.

Known label variations for U1170:

• U1170 — SCP (J1850) Invalid or Missing Data for Cellular Phone / Paging System (Ford, Lincoln, Mercury)
• U1170 — SCP Data Fault Cellular Phone/Paging (Mazda)
• U1170 — Cellular Phone/Paging System Data Fault (Jaguar)

Summary of code U1170 #

U1170 is a communication-related diagnostic trouble code (DTC) that indicates the vehicle’s control modules are not receiving valid or expected data from the cellular phone or paging system over the SCP (Standard Corporate Protocol) J1850 network. This code is most commonly found in vehicles equipped with integrated telematics, hands-free calling, or factory cellular systems. When this code appears, it means that either the data is missing entirely or is corrupted, affecting the module-to-module communication. As a result, features relying on this data may not function as intended, but the vehicle’s core drivability is typically unaffected. However, this fault can hint at broader issues with the vehicle’s communication network or aftermarket modifications.

Common symptoms for code U1170 #

When U1170 is present, the symptoms are often subtle since the code targets non-essential communication systems. However, depending on the vehicle and its options, you may notice:

• Malfunction or unavailability of the built-in cellular phone or telematics system
• Warning messages or “no phone detected” alerts on the dashboard or infotainment display
• Loss of remote services (e.g., remote unlock, emergency call features)
• Occasional chimes or error tones after startup
• Other communication DTCs stored in related modules

Probable causes for code U1170 #

U1170 is almost always linked to communication problems, but several underlying issues can trigger this code. The causes, from most to least likely, include:

1. Faulty or disconnected cellular phone/paging module
2. Damaged, corroded, or loose wiring/connectors at the module or along the SCP (J1850) network
3. Aftermarket equipment installation disrupting the factory communication bus
4. Network-wide issues such as a short or open circuit on the SCP (J1850) data line
5. Failed or outdated software in the telematics or body control module
6. Blown fuse or insufficient power/ground to the module

Step-by-step diagnosis for code U1170 #

A systematic approach is key to pinpointing the cause of U1170. Always follow proper safety procedures and consult your OEM service manual. Here’s a proven workflow:

• Verify the code with a scan tool and note any additional DTCs in other modules.
• Check if the cellular/telematics system is present and enabled (not all vehicles are equipped, or the option may be disabled).
• Inspect all related fuses and relays for the telematics/phone system.
• Examine the physical connections at the cellular/paging module—look for corrosion, bent pins, or loose connectors.
• Check the SCP (J1850) wiring for continuity, shorts, or signs of damage, especially if any aftermarket equipment is installed.
• Use a scan tool to attempt communication with the affected module. If communication fails, the module or wiring may be at fault.
• Test power and ground supplies at the module using a multimeter.
• If all wiring checks out, consider reprogramming or updating the telematics/module software as per OEM recommendations.
• Replace the module only after confirming all other steps, as misdiagnosis is common.

Possible repairs for code U1170 #

Repairs for U1170 focus on restoring reliable communication and module function. Depending on what you find during diagnosis, the following fixes may be necessary:

• Reconnect or replace loose, corroded, or damaged wiring/connectors
• Replace blown fuses or restore proper power/ground to the module
• Remove or correctly integrate aftermarket equipment interfering with the communication bus
• Update or reflash telematics/module software as per OEM instructions
• Replace the cellular phone/paging module if confirmed faulty
• Repair or replace sections of the SCP (J1850) data line if wiring faults are found

Is it safe to drive with code U1170? #

Yes, in most cases, you can continue to drive with code U1170 present. This DTC typically does not affect core vehicle performance, engine operation, or safety systems. The main impact is the loss or malfunction of cellular/telematics features. However, if your vehicle uses these systems for emergency services or remote unlocking, those features may not work until the issue is resolved. Always address wiring and network issues promptly to prevent escalation or the appearance of additional DTCs.

Vehicles most commonly affected by code U1170 #

U1170 is most frequently encountered in vehicles from manufacturers who integrated early telematics or cellular communication systems into their platforms, especially in the 2000s and early 2010s. The following vehicle lines are most likely to report this DTC:

• Ford (Fusion, Taurus, Expedition, Explorer, F-150, Escape, etc.)
• Lincoln (MKZ, Navigator, Town Car, etc.)
• Mercury (Milan, Mountaineer, etc.)
• Mazda (models sharing Ford platforms, e.g., Tribute)
• Jaguar (select models with Ford-supplied electronics)

Common mistakes & best practices for code U1170 #

Misdiagnosis is common with U1170 due to its networked nature. Avoid these pitfalls and follow best practices for efficient repair:

• Assuming the module is faulty without checking power, ground, and network wiring first
• Overlooking the impact of aftermarket alarms, remote starters, or telematics devices
• Ignoring other related communication codes that could provide valuable clues
• Replacing parts before performing a thorough visual inspection of connectors and harnesses
• Failing to update module software when recommended by the OEM

Express FAQ for code U1170 #

Here are quick answers to common questions about code U1170:

• Q: Will U1170 cause my vehicle to stall or not start?
  A: No, U1170 affects only the communication with the cellular/telematics system. Your engine and transmission will operate normally.
• Q: Can I clear U1170 with a scan tool and ignore it?
  A: You can clear the code, but if the root cause isn’t fixed, it will return. The telematics or phone system will not work correctly until the communication problem is repaired.