Code
U1116
HYUNDAI
U — Network/User
Lost Communication With Motor Electronics Coolant Pump (C-CAN)
Views:
UK: 12
EN: 17
RU: 20
AI status
Completed
Completed
100%
Causes
- Open or short in CAN H/L wiring to the coolant pump module
- Corroded/loose connector at the coolant pump or junction box
- Faulty coolant pump motor electronics / module
- Blown fuse or lost supply/ground to the pump module
- CAN bus short to chassis or battery voltage (CAN H or CAN L shorted)
- Missing or failed CAN termination resistor(s)
Symptoms
- Malfunction indicator lamp (MIL) or message and U1116 stored in memory
- Coolant pump not operating when expected or running in limp/default mode
- Reduced cooling performance or overheating under some conditions
- Related modules reporting multiple CAN comm errors or network faults
- No CAN frames received from pump node when scanned with a diagnostic tool
What to check
- Retrieve freeze frame and network scan results with a capable scan tool
- Visual inspection of coolant pump connector and harness for corrosion, damage, or water intrusion
- Verify fuses/relays supplying the pump and related junction box are intact
- Check battery voltage and charging system for adequate voltage (11–14.5 V expected)
- Inspect for diagnostic trouble codes in other CAN modules that indicate a bus issue
- Confirm ground continuity for the pump module to chassis
Signal parameters
- CAN High (idle): ~2.5 V (oscillating around this value when network active)
- CAN Low (idle): ~2.5 V (oscillating inversely to CAN High)
- CAN differential: dominant pulses typically ~1.0–2.0 V differential during transmission
- Bus idle differential ~0 V (small noise), bus resistance ≈ 60 Ω with two 120 Ω terminators
- Module supply to pump: approx. battery voltage (11–14.5 V) when key On
- Expected CAN message periodicity: nodes commonly transmit periodic status frames (tens to hundreds of ms). Absence of expected periodic frames from the pump node indicates lost comms.
Diagnostic algorithm
- Use a network scan tool to confirm U1116 and check for other U-codes or module absences on C‑CAN.
- Record conditions when the code set (key on/off, engine running, temperatures). Try clearing the code and see if it returns and under what conditions.
- Visually inspect the coolant pump connector and harness for corrosion, bent pins, damage, or water entry. Repair any obvious issues.
- Verify power and ground at the pump connector with key ON: battery voltage at supply pin and good ground continuity. Repair supply/ground faults before proceeding.
- Check related fuses and relays in the junction box that feed the pump module; replace if open.
- Backprobe or access the CAN H and CAN L at the pump connector or nearest junction. With an oscilloscope check for proper CAN waveforms and differential activity while key ON and during cranking.
- Measure resistance between CAN H and CAN L with ignition off — expect ≈ 60 Ω. If open or very high/low, isolate by disconnecting segments or modules to locate the fault.
- Disconnect the coolant pump module and observe if the rest of the bus recovers (other modules communication restored). If disconnecting the pump clears other network errors, suspect pump module or its wiring as the fault.
- If wiring and supply/ground are good but no communication from the pump, consider replacing or reprogramming the pump motor electronics per manufacturer procedures.
- After repairs, clear codes and perform a functional test and network scan to confirm the U1116 does not return and that the pump responds to commands.
Likely causes
- Damaged connector or wiring at the coolant pump (most common on routed harnesses)
- Loss of module supply power or ground at the pump
- Failed pump motor electronics (module internal fault)
- Shorted CAN pair or high resistance on the CAN bus
- Failed termination resistor or other module pulling the bus down
Fault status
Status
Lost communication with Motor Electronics Coolant Pump (C‑CAN). CAN messages from the coolant pump module are not being received. Inspect wiring, power/ground, connectors, and CAN bus integrity.
Repair difficulty: Medium
Diagnostic time: 1.0-2.5 hours
Similar codes
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email
Code
U1116
MITSUBISHI
U — Network/User
KOS CAN timeout/Not equipped
Views:
UK: 8
EN: 15
RU: 19
AI status
Completed
Completed
100%
Causes
- Open or short in CAN H/L wiring to the coolant pump module
- Corroded/loose connector at the coolant pump or junction box
- Faulty coolant pump motor electronics / module
- Blown fuse or lost supply/ground to the pump module
- CAN bus short to chassis or battery voltage (CAN H or CAN L shorted)
- Missing or failed CAN termination resistor(s)
Symptoms
- Malfunction indicator lamp (MIL) or message and U1116 stored in memory
- Coolant pump not operating when expected or running in limp/default mode
- Reduced cooling performance or overheating under some conditions
- Related modules reporting multiple CAN comm errors or network faults
- No CAN frames received from pump node when scanned with a diagnostic tool
What to check
- Retrieve freeze frame and network scan results with a capable scan tool
- Visual inspection of coolant pump connector and harness for corrosion, damage, or water intrusion
- Verify fuses/relays supplying the pump and related junction box are intact
- Check battery voltage and charging system for adequate voltage (11–14.5 V expected)
- Inspect for diagnostic trouble codes in other CAN modules that indicate a bus issue
- Confirm ground continuity for the pump module to chassis
Signal parameters
- CAN High (idle): ~2.5 V (oscillating around this value when network active)
- CAN Low (idle): ~2.5 V (oscillating inversely to CAN High)
- CAN differential: dominant pulses typically ~1.0–2.0 V differential during transmission
- Bus idle differential ~0 V (small noise), bus resistance ≈ 60 Ω with two 120 Ω terminators
- Module supply to pump: approx. battery voltage (11–14.5 V) when key On
- Expected CAN message periodicity: nodes commonly transmit periodic status frames (tens to hundreds of ms). Absence of expected periodic frames from the pump node indicates lost comms.
Diagnostic algorithm
- Use a network scan tool to confirm U1116 and check for other U-codes or module absences on C‑CAN.
- Record conditions when the code set (key on/off, engine running, temperatures). Try clearing the code and see if it returns and under what conditions.
- Visually inspect the coolant pump connector and harness for corrosion, bent pins, damage, or water entry. Repair any obvious issues.
- Verify power and ground at the pump connector with key ON: battery voltage at supply pin and good ground continuity. Repair supply/ground faults before proceeding.
- Check related fuses and relays in the junction box that feed the pump module; replace if open.
- Backprobe or access the CAN H and CAN L at the pump connector or nearest junction. With an oscilloscope check for proper CAN waveforms and differential activity while key ON and during cranking.
- Measure resistance between CAN H and CAN L with ignition off — expect ≈ 60 Ω. If open or very high/low, isolate by disconnecting segments or modules to locate the fault.
- Disconnect the coolant pump module and observe if the rest of the bus recovers (other modules communication restored). If disconnecting the pump clears other network errors, suspect pump module or its wiring as the fault.
- If wiring and supply/ground are good but no communication from the pump, consider replacing or reprogramming the pump motor electronics per manufacturer procedures.
- After repairs, clear codes and perform a functional test and network scan to confirm the U1116 does not return and that the pump responds to commands.
Likely causes
- Damaged connector or wiring at the coolant pump (most common on routed harnesses)
- Loss of module supply power or ground at the pump
- Failed pump motor electronics (module internal fault)
- Shorted CAN pair or high resistance on the CAN bus
- Failed termination resistor or other module pulling the bus down
Fault status
Status
Lost communication with Motor Electronics Coolant Pump (C‑CAN). CAN messages from the coolant pump module are not being received. Inspect wiring, power/ground, connectors, and CAN bus integrity.
Repair difficulty: Medium
Diagnostic time: 1.0-2.5 hours
Similar codes
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email
Code
U1116
Other
U — Network/User
SCP (J1850) Invalid or Missing Data for Electrical Energy Management
Views:
UK: 17
EN: 24
RU: 24
AI status
Completed
Completed
100%
Causes
- Open or short in CAN H/L wiring to the coolant pump module
- Corroded/loose connector at the coolant pump or junction box
- Faulty coolant pump motor electronics / module
- Blown fuse or lost supply/ground to the pump module
- CAN bus short to chassis or battery voltage (CAN H or CAN L shorted)
- Missing or failed CAN termination resistor(s)
Symptoms
- Malfunction indicator lamp (MIL) or message and U1116 stored in memory
- Coolant pump not operating when expected or running in limp/default mode
- Reduced cooling performance or overheating under some conditions
- Related modules reporting multiple CAN comm errors or network faults
- No CAN frames received from pump node when scanned with a diagnostic tool
What to check
- Retrieve freeze frame and network scan results with a capable scan tool
- Visual inspection of coolant pump connector and harness for corrosion, damage, or water intrusion
- Verify fuses/relays supplying the pump and related junction box are intact
- Check battery voltage and charging system for adequate voltage (11–14.5 V expected)
- Inspect for diagnostic trouble codes in other CAN modules that indicate a bus issue
- Confirm ground continuity for the pump module to chassis
Signal parameters
- CAN High (idle): ~2.5 V (oscillating around this value when network active)
- CAN Low (idle): ~2.5 V (oscillating inversely to CAN High)
- CAN differential: dominant pulses typically ~1.0–2.0 V differential during transmission
- Bus idle differential ~0 V (small noise), bus resistance ≈ 60 Ω with two 120 Ω terminators
- Module supply to pump: approx. battery voltage (11–14.5 V) when key On
- Expected CAN message periodicity: nodes commonly transmit periodic status frames (tens to hundreds of ms). Absence of expected periodic frames from the pump node indicates lost comms.
Diagnostic algorithm
- Use a network scan tool to confirm U1116 and check for other U-codes or module absences on C‑CAN.
- Record conditions when the code set (key on/off, engine running, temperatures). Try clearing the code and see if it returns and under what conditions.
- Visually inspect the coolant pump connector and harness for corrosion, bent pins, damage, or water entry. Repair any obvious issues.
- Verify power and ground at the pump connector with key ON: battery voltage at supply pin and good ground continuity. Repair supply/ground faults before proceeding.
- Check related fuses and relays in the junction box that feed the pump module; replace if open.
- Backprobe or access the CAN H and CAN L at the pump connector or nearest junction. With an oscilloscope check for proper CAN waveforms and differential activity while key ON and during cranking.
- Measure resistance between CAN H and CAN L with ignition off — expect ≈ 60 Ω. If open or very high/low, isolate by disconnecting segments or modules to locate the fault.
- Disconnect the coolant pump module and observe if the rest of the bus recovers (other modules communication restored). If disconnecting the pump clears other network errors, suspect pump module or its wiring as the fault.
- If wiring and supply/ground are good but no communication from the pump, consider replacing or reprogramming the pump motor electronics per manufacturer procedures.
- After repairs, clear codes and perform a functional test and network scan to confirm the U1116 does not return and that the pump responds to commands.
Likely causes
- Damaged connector or wiring at the coolant pump (most common on routed harnesses)
- Loss of module supply power or ground at the pump
- Failed pump motor electronics (module internal fault)
- Shorted CAN pair or high resistance on the CAN bus
- Failed termination resistor or other module pulling the bus down
Fault status
Status
Lost communication with Motor Electronics Coolant Pump (C‑CAN). CAN messages from the coolant pump module are not being received. Inspect wiring, power/ground, connectors, and CAN bus integrity.
Repair difficulty: Medium
Diagnostic time: 1.0-2.5 hours
Similar codes
Workshop Manuals
Available brands with manuals
2
AUDI 11
6-speed manual gearbox 0B1, front-wheel drive — Workshop Manual (Edition 05.2014)
Workshop ManualAudi A3 (1997) – 1.6L 4-cylinder (2‑valve) Engine Mechanical Components Service Manual (AEH, AKL, APF) – Edition 07.2002
Workshop ManualAUDI A3 (2004) Workshop Manual — 2.0L FSI Turbo (4‑cyl, 4‑valve) Engine, Mechanics — Edition 03.2017
Workshop ManualAudi A3 2004 — Electrical System (Workshop Manual, Edition 02.2018)
Workshop ManualAudi A4 / A4 Cabriolet – 4.2 l V8 (5‑valve, timing chains) – Workshop Manual (Mechanics) – Edition 04.2007
Workshop ManualAudi A4 / A4 Cabriolet — Auxiliary Heater Workshop Manual (Edition 08.2004)
Workshop ManualAudi A4 / A4 Cabriolet (1.8T 4‑cyl turbo) — Motronic Injection & Ignition System Service Manual (Edition 01.2015)
Workshop ManualAudi A8 (2003) — Electrical System Workshop Manual (Edition 08.2014)
Workshop ManualAudi Q4 e-tron (Type F4) - Self-study Programme SSP 685
Workshop ManualAudi Q8 (2018) — Electrical System Workshop Manual (Edition 05.2019)
Workshop ManualAudi Servicing Manual — 7‑Speed Dual Clutch Transmission 0CJ / 0CL / 0CK / 0DN / 0DP / 0HL (Edition 05.2018)
Workshop ManualLAND ROVER 3
Land Rover Defender 300Tdi — Workshop Manual (1996 model year)
Workshop ManualLand Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)
Workshop ManualLand Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)
Workshop ManualYour experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email
