P1627

Code

DS P — Powertrain

Inside ECU (CAN)

Brand: DS

Type: P — Powertrain

Views: UK: 0 EN: 2 RU: 1

AI status

Completed

ready

Completed 100%

Page language: EN

Open or short in CAN high/low wiring between inside ECU and network
Poor power supply or ground to the inside ECU (battery, ignition feed, ground strap)
Corroded/poor connector pins at the inside ECU or harness
Blown fuse or relay feeding the inside ECU
CAN bus nodes interfering (multiple nodes with same ID) or bus termination fault
Internal fault in the inside ECU (hardware or corrupted software)

One or more interior functions controlled by the inside ECU work intermittently or not at all (climate, lights, door locks, infotainment integration, etc.)
MIL or multiple warning lights illuminated related to communications
Stored communication DTCs (P1627 and possibly other network/communication codes)
Loss of data or parameters from inside ECU on live-data stream
Functions work after key cycles or go intermittent depending on vehicle movement

Use a scan tool to read all stored and pending DTCs on all networks; note related U- and B-codes
Verify whether the inside ECU appears on the vehicle network (module present in scan tool list)
Check battery voltage and health; measure with engine off and during cranking
Visually inspect fuses and relays for the inside ECU power circuits
Inspect inside ECU connector for corrosion, bent pins, water ingress or damaged locking tangs
Check for recent body or wiring work in the passenger compartment related to the inside ECU harness

CAN bus messages from inside ECU (presence/absence of expected message IDs)
CAN bus error/frame rate (error frames per second, bus-off events)
CAN bus voltage waveform (differential activity and recessive voltage stability)
Supply voltage to inside ECU (nominal battery voltage; stable within ~12–14.5 V when running)
Ground continuity from inside ECU ground pin to chassis
Fuse continuity for inside ECU feed(s)

Connect a capable scan tool and record freeze-frame and all related fault codes on all networks; note timestamps
Verify whether the inside ECU module is detected. If not detected, check for related U-codes (lost communication)
With ignition on, verify supply voltage at inside ECU power pins and continuity to fuse/relay; repair any open/low-supply issues
Check ground(s) for low resistance to chassis; clean and secure grounds if needed
Visually inspect and, if practical, unplug/replug the inside ECU connector; check for corrosion or bent pins; repair as necessary
Inspect CAN high/low wiring for damage, pinouts, and proper termination; measure for continuity and shorts to battery/ground using multimeter (engine off)
If wiring appears OK, use an oscilloscope or CAN bus analyzer to view CAN_H and CAN_L waveforms while operating vehicle functions; look for missing messages, bus noise, dominant/recessive voltages and error frames
If the inside ECU messages are absent but bus signals from other modules are present, suspect inside ECU failure or its software; consult manufacturer service information for reprogramming/parameterization steps before replacement
If multiple modules report communication errors, locate and repair shared wiring or common junction points (splices, junction boxes)
After repairs, clear codes, re-test all affected functions and verify normal CAN traffic and no recurrence of P1627; perform any required initialization or module programming

⚠️ Status

P1627 - Inside ECU CAN communication fault (Inside ECU not communicating correctly on CAN bus)

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1-3 hours

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

P1627 — Inside ECU (CAN)