P2508

Code

LAND ROVER P — Powertrain

Power input signal of the engine control module / module high power train control

Brand: LAND ROVER

Type: P — Powertrain

Views: UK: 19 EN: 90 RU: 22

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Blown or corroded fuse(s) protecting ECM/high-power module
Faulty ignition or power relay (ECM supply relay)
Low battery voltage or poor battery connections
Open, short to ground, or short to battery in the supply harness or connector
Poor or corroded ground connection(s) for the ECM/module
Damage/corrosion at module connector or pins

Symptoms

Malfunction Indicator Lamp (MIL) or fault light illuminated
Engine may not start or cranks but does not run
Intermittent loss of engine power or stalling
Loss of communication with ECM via diagnostic tool
Various drivability faults or limp-home mode
Accessories or fuel system not powered when ignition ON

What to check

Read and record all DTCs and freeze-frame data with a capable scan tool; check for related codes
Inspect battery state-of-charge and measure resting voltage (should be ~12.4–12.8 V) and charging while running (~13.5–14.8 V)
Visually inspect fuses, fusible links and relays for damage or corrosion; verify correct fuse ratings
Check battery terminals and main chassis/engine grounds for tightness and cleanliness
Inspect ECM/module connector for corrosion, bent/burnt pins, or water ingress
Using wiring diagrams, identify ECM power input pin(s) and measure voltage with key ON and while cranking

Signal parameters

Expected supply voltage at ECM power pin with ignition ON: approximately battery voltage (~11–14.5 V)
Voltage during cranking: typically >9 V (depends on battery/engine starter load)
Supply wire continuity: near 0 ohms (
Ground resistance: very low (
Fuse rating: check service data for the correct amperage (common main ECU fuses range from 5 A to 30 A or include fusible links)
No significant voltage drop under load between battery and ECM power input (drop should be minimal, typically

Diagnostic algorithm

Confirm code: Connect a manufacturer-capable scan tool, record P2508 and any supporting/related codes and freeze frame data.
Battery & basics: Verify battery voltage and state of charge; clean/tighten battery terminals and main grounds.
Fuses/relays: Locate and inspect all fuses and relays for ECM/high-power module supply. Replace suspicious items and re-test.
Visual harness inspection: Inspect wiring from battery/relay/fuse to ECM for damage, heat, or corrosion. Repair any damaged wiring or connectors.
Voltage check: Identify ECM power input pin from wiring diagram. With ignition ON measure voltage at that pin. Repeat while cranking. No or low voltage indicates supply fault upstream.
Continuity/short tests: With battery disconnected, check continuity from ECM power pin back to fuse/relay and to battery. Check for shorts to ground from the supply circuit.
Ground integrity: Measure resistance between ECM ground pins and battery negative/chassis. Clean or repair ground points if high resistance found.
Relay and control: If supply is controlled by a relay, verify relay coil and contact operation (apply 12 V to coil and check contact continuity or use scan tool to command relay if supported).
Re-test and monitor: After repairs, clear codes and perform a road or start-up test while monitoring live data and voltage at the ECM; verify code does not return.
Module consideration: If wiring, power, grounds and related components verify good, consider module fault. Confirm software level/TSBs and consult manufacturer procedures before replacing ECM/module.

Likely causes

Blown main ECU power fuse or fusible link
Intermittent ignition/power relay contact or stuck relay
Loose/oxidized battery negative or positive terminal
Open supply wire between battery/relay and ECM power pin
Short to ground on ECM supply circuit
Damaged connector pins (burnt/melted) at ECM

Fault status

⚠️ Status

P2508 — Power input to Engine Control Module / High Power Train Control module is missing or out of range. Inspect battery, fuses/relays, harness and module power/ground circuits.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1-3 hours

Similar codes

Repair manuals

Manual library for LAND ROVER

413

Browse 413 LAND ROVER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

LAND ROVER

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

P2508 — Power input signal of the engine control module / module high power train control