C2700

Code

Generic C — Chassis

Chassis Control Module Power Supply Circuit Malfunction

Brand: Generic

Type: C — Chassis

Views: UK: 10 EN: 12 RU: 8

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Blown or corroded fuse(s) supplying the CCM
Loose, corroded or damaged CCM connector or wiring harness
Poor engine/chassis ground to CCM
Battery low voltage or poor battery/charging system
Short to battery or short to ground in the CCM supply circuit
Intermittent connection (water intrusion, chafing, broken wire)

Symptoms

CCM-related functions inoperative or intermittent (doors, lighting, stability/traction assist, etc.)
Related warning lamps or messages (chassis, stability, ABS, vehicle systems)
Loss of communication between CCM and other modules (CAN/U‑bus messages)
Electrical accessories fail or behave erratically
Parasitic battery drain or fuse repeatedly blowing

What to check

Read stored freeze frame data and all related U/C/B/C codes with a scan tool
Visually inspect fuses, fusible links, CCM connector and harness for corrosion, damage, pin push‑out or water
Check battery state of charge and charging system (resting voltage and alternator output)
Check fuse continuity and replace suspected blown fuses with correct rating (do not bypass fuse)
Backprobe CCM power and ground pins with key OFF and key ON and while operating affected circuits
Measure voltage at the CCM supply pin(s) and compare to battery voltage (with connector connected)

Signal parameters

Battery resting voltage: typically ~12.4–12.8 V (engine off, charged battery)
Charging voltage: typically ~13.5–14.8 V (engine running)
CCM supply (ignition ON): within ~0.5 V of battery voltage (allow for wiring drop)
Voltage during cranking: not less than ~9.0 V at module connector
Ground loop/return resistance:
CAN bus recessive level (if applicable): ~2.5 V per line; CANH ~2.5–3.5 V, CANL ~1.5–1.8 V (verify with manufacturer spec)

Diagnostic algorithm

Capture freeze frame and all codes; note conditions when C2700 set (key position, engine running, load).
Verify battery health and charging system: record resting voltage, cranking voltage, and alternator output. Repair battery/charging if out of spec.
Visually inspect CCM connector, pins and harness for corrosion, bent pins, water intrusion or physical damage. Repair or replace damaged connector/harness as needed.
Check fuses/fusible links supplying the CCM. Replace blown fuses with correct rating and retest. If fuse blows again, suspect short — do not repeatedly replace without diagnosing short.
With a DVOM or lab scope, backprobe CCM supply pin(s) and measure voltage with key OFF, key ON, engine running and during faults. Compare to battery voltage. Look for drops, spikes or intermittent loss.
Measure resistance/continuity between CCM ground pins and chassis/battery negative. Clean and tighten ground connections if resistance is high.
If supply behaves intermittently, perform a wiggle test on harness while monitoring voltage and module status; isolate the harness section causing change.
If short suspected, isolate by removing/inspecting branches or disconnecting downstream loads and measuring for continuity to battery/ground; use fused jumper or current-limited bench supply for safe testing.
Verify CAN/bus communications at CCM if related network faults present. Repair bus wiring or bus termination issues if necessary.
If wiring, fuses and grounds are good and supply still out of range, consider module internal power stage failure. Confirm with manufacturer test procedures; replace or reprogram CCM only after harness verified.
Clear codes and perform functional test cycles and road test to confirm repair; monitor for recurrence.