If you drive a 2004 Dodge Ram, chances are you’ve come across the mysterious “C Code” messages that show up in the odometer when running the cluster self-test.
The 2004 Dodge Ram C Code List identifies instrument cluster and chassis faults, such as 01 (airbag indicator shorted) or 64 (driver door lock switch open), allowing owners to diagnose electrical, lighting, and communication issues quickly.
In this guide, we’ll break down the complete 2004 Dodge Ram C Code list, explain how to pull them, and share fixes that actually work.
What are “C-codes” on a 2004 Ram?
On Chrysler/Dodge products, OBD-II diagnostic trouble codes are grouped by system:
- P = Powertrain,
- B = Body,
- C = Chassis,
- U = Network/communication.
When you run the instrument cluster self-test on a 2004 Dodge Ram 1500/2500/3500, the odometer will show “C Code” messages if the cluster detects issues with indicator outputs, door lock circuits, wiper/washer inputs, PCI bus messages, etc.
These are not engine P-codes and won’t tell you why the truck misfires. Think of them as cluster/chassis status flags that help you chase wiring, switch, and module-to-module communication problems.
How to pull C-codes on a 2004 Ram (no scan tool)
- Sit in the truck and close all the doors.
- Press and hold the trip/odometer button.
- Turn the key to RUN (do not start the engine).
- Release the button when the cluster sweeps; watch the odometer window.
- The display will show any “C Code” entries in sequence (e.g., C Code 05, C Code AA).
- When finished, it will show “00” or “Done.”
- This exact procedure and the code list come from long-standing Ram forum documentation and technician write-ups.
Pro tip: To read engine P-codes without a scanner, use the classic key-cycle trick (OFF→RUN three times, ending in RUN) and look for P0xxx in the odometer. That’s separate from cluster C-codes.
Complete 2004 Dodge Ram C Code List (with plain-English meaning)
The list below is consolidated from Chrysler/Ram cluster documentation used by owners and techs. Use it as your quick reference while diagnosing.
1. Indicator and warning lamp circuits
- 01 – Airbag (SRS) warning indicator output circuit shorted
- 02 – Airbag (SRS) warning indicator output circuit open
- 03 – ABS indicator output circuit shorted
- 04 – ABS indicator output circuit open
- 05 – MIL/Check-Engine indicator output circuit shorted
- 06 – MIL/Check-Engine indicator output circuit open
- 07 – “Wait-to-Start” lamp circuit shorted (diesel)
- 08 – “Wait-to-Start” lamp circuit open
- 0B – BTSI (brake-transmission shift interlock) output circuit short/open
2. Lighting, wiper, washer inputs
- 22 – Headlamp switch input shorted
- 23 – Headlamp switch input open
- 24 – Turn/hazard switch input shorted
- 25 – Turn/hazard switch input open
- 27 – Courtesy/dome lamp output short/open
- 28 – Glovebox/map lamp output short/open
- 29 – Cargo lamp output short/open
- 40 – Wiper switch input shorted
- 41 – Wiper switch input open
- 42 – Washer/beam input shorted
3. Door locks / remote switches
- 60 – Passenger door-lock switch input shorted
- 61 – Passenger door-lock switch input open
- 62 – Passenger door-lock switch input stuck
- 63 – Driver door-lock switch input shorted
- 65 – Driver door-lock switch input stuck
- 66 – All-door lock output shorted to ground/voltage
- 67 – All-door unlock output shorted to ground/voltage
- 68 – Driver-door unlock output shorted to ground/voltage
- 6C – Driver cylinder-lock switch input shorted
- 6E – Driver cylinder-lock switch input stuck
4. Odometer/radio/cluster internal and comms
- 80 – Incorrect odometer value found
- 81 – Remote radio switch input high
- 82 – Remote radio switch stuck
- A0 – Internal module FLASH checksum failure
- A1 – Internal module bootloader failure
- A3 – Cluster battery voltage open/loss
- A5 – TCCM (transfer case control) messages not received
- A7 – VIN checksum error
- A8 – VIN previously stored (VIN mismatch event)
- A9 – PCI bus internal failure
- AA – PCM messages not received
- AB – TCM messages not received
- AC – ABS messages not received
- AD – FCM (front control module) messages not received
- AE – ACM messages not received
- AF – SKIM (Sentry Key Immobilizer) messages not received
- B0 – RKE (key fob) batteries are low
- B1 – RKE module communication link fault
- 00 – Done (no more C-codes)
What C-codes do—and don’t—tell you
- They do flag cluster outputs/inputs and module-to-module comms on the truck’s PCI bus (e.g., PCM⇄cluster).
- They don’t replace a scan-tool session. If the car won’t start and you see AA/AB/AC (no messages from PCM/TCM/ABS), the real problem might be a power/ground issue to a module, a PCI bus short, a faulty TIPM/FCM, or a dead PCM. You’ll still need scan-tool comms and electrical testing.
Year fitment note: Why this applies to 2004
The 2003–2005 (3rd-gen) Ram cluster runs the same self-test and shows the same C-codes in the odometer, which is why you’ll see owners of 2003–2005 trucks quoting the same list. Your 2004 uses this exact scheme.
Field-tested fixes for the most common C-codes
1. C-codes 05/06 (MIL lamp output open/short)
What it means: The cluster can’t drive the MIL lamp line correctly.
Likely causes: Burned bulb/LED issue (early clusters), printed-circuit fault, short to ground/12V in the lamp feed, or an internal cluster driver fault.
What to do:
- Run the cluster self-test again to verify the lamp sweep.
- Inspect the cluster connector for bent pins/corrosion; reseat.
- Check the MIL control line for continuity/shorts.
- If outputs test good and the line is clean, consider cluster repair/replacement.
2. 22/23/24/25/40/41/42 (switch inputs open/short)
What it means: The cluster is seeing impossible voltages on headlamp/turn/hazard/wiper/washer inputs.
Likely causes: Failing multi-function switch, rubbed-through column harness, water in the junction block, or a bad ground.
What to do:
- Wiggle-test the multi-function switch harness while watching the odometer.
- Check the clock spring and column connectors for proper alignment.
- Inspect the fuse block/junction block for corrosion.
- Replace a known-bad combination switch if inputs don’t normalize.
3. 60–68 / 6C / 6E (door lock inputs/outputs)
What it means: Stuck/shorted door-lock switches or outputs to the actuators are out of range.
Likely causes: Sticky switches, failed actuator, harness break in door jamb, or short to ground/12V.
What to do:
- Pop the switch panel; check the switch resistance values.
- Inspect the door-jamb boot for broken wires.
- Compare the command locks from the RKE and the switch.
- Replace the actuator if it draws excessive current or is seized.
4. 80 (incorrect odometer value)
What it means: Cluster sees a mismatch or corrupted stored mileage data.
What to do:
- Confirm that the VIN stored in the cluster matches the one in the PCM (see A7/A8 notes).
- If the cluster or PCM was replaced, a dealer or a capable shop can reprogram the mileage/VIN according to local regulations.
5. A5 / AA / AB / AC / AD / AE / AF (module messages not received)
What it means: On the PCI bus, the cluster isn’t hearing from the named module (TCCM, PCM, TCM, ABS, FCM, ACM, SKIM).
Why it matters: These are the big ones when the truck won’t crank, gauges die, or multiple lights are on.
Game plan that works:
- Check each fuse that feeds the affected module(s).
- Verify grounds—especially battery-to-block and module ground pigtails.
- Unplug a suspect module and check if the bus communications return (a shorted module can pull the PCI low).
- If you can’t connect with a scan tool and the MIL will not power out, suspect PCM/TCM power/ground or a failed module.
6. B0 / B1 (RKE low battery / RKE link)
- Replace the key-fob batteries first.
- If B1 persists, check the RKE antenna/module connections and resync the fob.
Step-by-step: My reliable workflow for C-codes
- Pull C-codes with the cluster test and write them down in order.
- Also, perform the key-cycle for P-codes; note any powertrain faults.
- Battery/charging baseline: 12.6 V engine off, 13.8–14.6 V running.
- Check fuses & grounds feeding any module named by A-series C-codes.
- Wiggle-test suspect switches/harness runs (column, door boots, cluster plug).
- Scan-tool pass: Confirm you can communicate with the PCM/TCM/ABS/FCM/SKIM. If a module is “no comm,” isolate PCI wiring and module power/ground before replacing anything.
C-codes vs. P/B/U codes (clearing up the confusion)
- C-codes you see in the odometer after a cluster self-test are cluster/chassis messages—often helpful, sometimes just informational.
- P-codes (e.g., P0440) are genuine OBD-II faults related to emissions/engine/trans and can also be displayed on the odometer using the key-cycle trick.
- B- and U-codes exist, too, but generally require a scanner to retrieve fully.
- If you only chase C-codes when the truck stalls or won’t start, you may miss the real problem in the PCM or fuel system—that’s why technicians stress the importance of using a capable scan tool whenever communication appears to be offline.
2004 Dodge Ram C Code List PDF
The 2004 Dodge Ram C Code List PDF provides a comprehensive list of cluster test codes, each accompanied by a clear and concise explanation. Owners use it to check electrical, lighting, door lock, and communication issues without a scanner, making troubleshooting easier.
Dodge Ram C code 00 00
When your Dodge Ram displays C code 00 00, it indicates that the cluster test found no stored faults. This is a “clean bill” for the instrument panel and connected circuits—no errors detected at that time.
Dodge Ram C-code reset
You can’t reset C-codes like engine codes. Instead, repair the issue and rerun the cluster self-test. Once the fault is gone, the C-code won’t reappear. A scan tool may also clear memory if needed.
Dodge Ram Instrument cluster codes
Instrument cluster codes in a Dodge Ram appear during the self-test when you hold the trip button and turn the key. They check lights, gauges, and communication circuits, providing owners with useful clues about potential electrical problems.
Dodge Ram C code AA
C Code AA on a Dodge Ram means the cluster isn’t receiving communication messages from the PCM (engine computer). It often causes dead gauges or warning lights to appear. Check fuses, wiring, and PCM power before replacing modules.
Dodge Ram C code A4
C Code A4 is uncommon but typically indicates an internal instrument cluster issue or memory problem. It may need professional inspection, reprogramming, or even replacement if the module can’t reliably communicate with other systems.
Dodge Ram code list PDF
A Dodge Ram code list PDF is a handy reference that shows both C-codes and their meanings. Many owners download it for quick troubleshooting when the cluster displays mysterious messages during the self-test procedure.
Dodge Ram C code 67
Code 67 indicates that the door unlock output circuit is shorted to ground or voltage. This often relates to a faulty door actuator, wiring issue, or switch problem. Inspect the driver’s door harness and actuator first.
FAQs
1. Are these C-codes the same on gas and diesel 2004 Rams?
Yes, gas and diesel Ram models share the same C-codes, except that diesel models include additional codes, such as the Wait-to-Start indicator.
2. My truck shows C Code AA, and the gauges are dead—what now?
C Code AA means no PCM communication. Check PCM fuses, wiring, grounds, and module power. A bad PCM may cause it.
3. Can I clear C-codes without a scanner?
Fix the problem and rerun the cluster test. If the issue’s gone, the C-code disappears naturally without using a scanner.
4. Do 2003 and 2005 Rams use the same C-code list?
Yes, 2003 through 2005 Dodge Rams use the same instrument cluster C-code list, with nearly identical meanings and troubleshooting steps.
5. Where’s the official Chrysler list?
Chrysler doesn’t publish it in manuals. The list comes from dealer service information and Dodge Ram owner forums, which technicians often reference.
Conclusion
In conclusion, the 2004 Dodge Ram C-Code List is a valuable tool for diagnosing electrical and communication problems without specialized equipment. While it won’t replace a scan tool, understanding these codes helps owners pinpoint common issues, check wiring, and take smarter steps toward faster, cost-effective repairs.