U1173

Code

Other U — Network/User

SCP (J1850) Invalid or Missing Data for Remote Button Control

Brand: Other

Type: U — Network/User

Views: UK: 28 EN: 46 RU: 28

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Dead or weak key fob battery
Faulty or unprogrammed key fob
Faulty remote receiver / RKE module
Power, ground, or fuse fault to receiver module
Damaged or corroded connector or wiring between receiver and network
Intermittent or noisy SCP/J1850 network communications

Symptoms

Remote lock/unlock, trunk release, or panic button does not operate the vehicle
Intermittent remote operation (works sometimes, then fails)
No RF indicator (lamp/LED) activity at the receiver when buttons are pressed
Stored U1173 and possibly other network communication U-codes
Vehicle may require key in door or ignition to lock/unlock

What to check

Attempt operation with a known-good spare key fob and with fob held close to vehicle receiver
Verify key fob battery voltage and replace if below spec (use fresh CR2032 or manufacturer battery)
Scan vehicle for U1173 and related U-codes; record freeze-frame and occurrence count
Inspect fuses and relay for receiver/power module circuits
Visually inspect receiver module connectors and wiring for corrosion, damage, or loose pins
Check module supply voltage and ground at the receiver/RKE module with a DVOM

Signal parameters

Key fob battery voltage: nominal ~3.0 V (coin cell); replace if significantly lower
Remote fob transmits RF bursts when a button is pressed (use RF sniffer to confirm transmission)
Receiver module requires stable 12 V supply and a good chassis/ground to operate
SCP/J1850 network should show valid remote-button message IDs/payloads on the bus when fob is used (monitor with capable scan tool)
If available, compare signal pattern and bus payload with a known-good vehicle or spare module

Diagnostic algorithm

Verify symptom: confirm remote fails from typical distances and with door open/closed. Try spare fob and repeat.
Replace or test the key fob battery and retest. If a spare fob works, program/replace the faulty fob.
Scan for U1173 and other U-codes. Note occurrence count and freeze data. Clear codes and attempt to re-create the fault.
Inspect fuses and check receiver module supply and ground at the connector. Repair any open or poor connections.
Perform a visual and wiggle test of the receiver/RKE module harness and connectors. Repair or replace damaged wiring/terminals.
Use a scan tool or bus analyzer to monitor SCP/J1850 traffic while pressing remote buttons. Look for no-message, malformed payloads, or CRC errors.
If the receiver shows no RF activity but the fob is known-good, inspect/replace the RF antenna or receiver module as applicable.
If network messages are present but the receiving module flags invalid data, update or reflash module software if technical service bulletins apply.
After repairs, clear codes, retest multiple times, and verify remote operation and that U1173 does not return. Document findings and any replaced parts.

Likely causes

Key fob battery is dead or very weak
Damaged key fob or unprogrammed spare fob
Poor power/ground at the remote receiver module
Connector corrosion or wiring damage between receiver and BCM/network
Faulty remote receiver module

Fault status

⚠️ Status

Invalid or missing remote button control data detected on SCP (J1850) network. Remote functions may not operate. DTC U1173 stored when remote button messages are not received or are malformed.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.0 hours