U0141 Code: Lost Communication With Body Control Module "A"
A body module labeled "A" went silent; on many trucks and SUVs it is the smart fuse box under the hood.
Unverified: this manufacturer-specific definition comes from a single source or varies by model. Confirm it with a brand-specific scan tool.
At a glance
Severity: Moderate
- Meaning
- Lost Communication With Body Control Module "A"
- System
- Module Communication · Network
- Safe to drive?
- With caution
- Typical repair cost
- $20–$1,400
- DIY difficulty
- Moderate
U0141 is the standard code for losing contact with body control module "A", used on vehicles whose body electronics are split across more than one module. Which physical module that is depends on the make: on Chrysler, Dodge, Jeep and Ram models it is typically the integrated power module (TIPM) or front control module that sits in the underhood fuse box, while other makers use the label for the main in-cabin body module. Because the underhood type contains the relays for the fuel pump, horn, wipers, headlamps and cooling fan, a failure can cause random electrical behavior, a crank-no-start or stalling. Heat, moisture and a poor main power connection at the box are the usual triggers. The meaning varies by manufacturer, so confirm which module is "A" in the service information for your vehicle.
Can I keep driving? If the engine starts reliably and the lights and wipers work, drive gently to a shop. If the car stalls, won't restart or the wipers or headlights act up, don't rely on it; get it towed or repaired first.
How to read U0141
- U Network
- 0 Generic (SAE)
- 1 Module Communication
- 41 Specific fault
Symptoms
- Engine cranks but won't start, or stalls because the fuel pump loses power
- Horn, wipers or headlights switching on by themselves
- Cooling fan running constantly or not at all
- Power windows and locks dead while the dash lights up normally
- Clicking relays or a buzzing from the underhood fuse box
- Faults that come and go with engine heat or after rain or a car wash
Possible causes
Ranked by how often each cause is behind this code (editorial estimate).
- Loose or corroded main power stud and cable at the fuse box/front module, or corroded battery terminals
- Internal failure of the integrated power module, often burnt relay contacts or cracked solder joints
- Water getting into the fuse box and module connectors from a missing cover or leaking seal
- Low battery voltage or voltage dips during cranking
- Damaged CAN wiring or corroded connector underneath the module
- On some makes "A" is the in-cabin body module, so the true fault is there
Diagnosis step by step
Find out which module is "A"
Check the service information or scan tool module list for your exact vehicle. Knowing whether "A" is the underhood power module or the in-cabin body module decides where you start testing.
Tools: OBD-II scanner
Check the main feed to the fuse box
Remove the cover and inspect the large battery cable on the stud of the underhood fuse box or front module. Clean it, torque the nut to spec and voltage-drop test from the battery post to the stud while cranking; more than about 0.2 V is too much.
Tools: Multimeter, Torque wrench, Pliers
Look for moisture and heat damage
Check the box and cover seals, look for water inside, melted plastic or discolored fuse and relay sockets. On models where the module can be unclipped, lift it and inspect the connectors underneath for green corrosion.
Tools: Flashlight, Screwdriver
Test the outputs that matter for starting
If the engine won't start, check whether the fuel pump gets power when the key is turned on; a pump that primes with jumper power but not through the module confirms a module relay fault. Shops use the scan tool's actuator tests to click each output.
Tools: Multimeter, OBD-II scanner
Verify CAN and grounds at the module
Confirm about 2.5 V on each CAN line at the module connector and a clean ground to the body or inner fender. If power, ground and bus are good and the module still won't answer, it is the module.
Tools: Multimeter
Replace with a correctly configured unit
Replacement power modules are often programmed with the VIN and option content; a unit that isn't set up can leave features dead or set new codes. Buy one configured for your VIN or have it programmed after installation.
Tools: OBD-II scanner
Where the parts are
- 1Battery
- 2Alternator
- 3Engine computer (ECM)
- 4CAN bus
- 5Transmission
- 6Wheel speed sensor
- 7High-voltage battery
Repair options & costs
| Repair | DIY? | Estimated cost |
|---|---|---|
| Clean and tighten battery terminals and main power stud | Yes | $20–$120 |
| Dry and clean module connectors, replace cover seal | No | $80–$250 |
| Replace failed relay (only where the box has serviceable relays) | Yes | $20–$150 |
| Replace integrated power/front control module (programming incl.) | No | $500–$1,400 |
Rough US estimates for parts and labor; shop rates vary by region. Not a quote.
Notes by brand
Jeep
On Jeep models with a TIPM or front control module, such as the Grand Cherokee and Wrangler, U0141 usually points to that underhood module. Fuel pump relay and wiper/horn problems from this module are widely reported.
Dodge
Dodge vehicles built with the TIPM, such as the Durango, Journey and Grand Caravan, often show U0141 together with random electrical faults and crank-no-start complaints traced to the TIPM.
Field data
| Jeep | 4 | Wrangler | |
|---|---|---|---|
| Dodge | 2 | Grand Caravan |
Source: NHTSA Complaints API (US government open data), analyzed by DTC mention.
Emissions / smog test impact
Depends
U0141 alone usually doesn't turn on the check engine light, so it rarely fails a smog check by itself. A safety inspection will fail the vehicle if lights, horn or wipers aren't working.
Frequently asked questions
What is the difference between U0140 and U0141?
U0140 refers to a single body control module. U0141 is used when the vehicle has several body modules labeled "A", "B" and so on, and which physical module is "A" varies by make, so always check the service information.
Why does my car stall with U0141?
On vehicles where "A" is the underhood power module, that module switches the fuel pump relay. If it resets or loses communication, the pump can lose power and the engine stalls or won't restart.
Can I just replace a relay?
Only if your fuse box has plug-in relays. Many integrated power modules have relays soldered to the circuit board, so the module must be repaired by a specialist or replaced.
Does a new power module need programming?
Usually yes. It needs the VIN and the vehicle's option list so it knows which outputs to control; an unprogrammed unit can leave features dead.
Sources
- SAE J2012 – Diagnostic Trouble Code Definitions
- ISO 15031-6 – Road vehicles, diagnostic trouble code definitions (EOBD)
- Manufacturer public service information (cross-checked)
- NHTSA Complaints API
- Methodology: How We Build Code Pages · Data Sources We Use · Editorial Policy