Dodge/Jeep/Chrysler PCM Repair

Dodge/Jeep/Chrysler PCM Repair — Troubleshooting Guide (SKU Group)

Important: Use this guide if you reinstalled your repaired Dodge/Jeep/Chrysler PCM and the problem is still happening.
Important: Please do not open/disassemble the PCM or force/probe connector pins (terminals can spread and cause new faults).

• Step 1: Confirm you have the correct PCM
  • Verify the part number on the PCM matches the vehicle/application (engine + year range).
  • If a “plug style” looks different than the original, stop—fitment may be wrong.
• Step 2: Battery and main power/ground
  • Battery fully charged + terminals clean/tight.
  • Check/clean the main engine ground(s) and battery-to-body ground.
  • Look for corrosion inside cable ends (hidden under insulation).
• Step 3: Fuse + relay checks (both fuse boxes)
  • Check all PCM/ECM/IGN/ASD fuses in the under-hood box and interior box.
  • Swap the ASD/Main relay with a known-good matching relay.
• Step 4: Connector and harness inspection
  • Unplug PCM connectors and inspect for bent/pushed pins, loose terminals, corrosion/green buildup, moisture.
  • Inspect harness routing near the battery, PDC/fuse box, and engine for rub-through.
• Step 5: If the issue is crank/no-start
  • Verify ASD relay powers up during crank.
  • Check crank sensor connection/wiring (common cause).
  • Confirm fuel pressure and spark/injector pulse during crank.
• Step 6: If it starts then stalls
  • Re-check ASD relay “hold” power while running.
  • Check security/immobilizer indicators/messages (some vehicles require programming steps if PCM was swapped).
• Step 7: If the issue is no communication / won’t scan
  • Confirm the diagnostic port has power/ground (a dead port can look like a dead PCM).
  • Check for a shorted module/wiring on the network that can block communication.
  • Disconnect aftermarket add-ons (remote start, radio taps, trackers) and re-test comms.
• Step 8: If the issue is limp mode / shifting complaints
  • Scan for codes and address sensor/network codes first (TPS, MAP, crank/cam, voltage, communication).
  • Re-check any sensor plugs that were recently serviced.
• Step 9: If symptoms started after other repairs
  • Re-check anything that was touched: grounds, fuse seating, relay seating, sensor connectors, harness routing.
• Step 10: Final “hidden issue” test
  • Have a shop perform voltage-drop tests on PCM power and grounds while cranking (finds resistance that basic checks miss).