What Does P1611 Mean?
The PCM has detected a short circuit to ground in the malfunction indicator lamp (MIL) control circuit that communicates with the transmission control module. This prevents proper MIL operation and module communication.
Common Causes
40%
Short to ground in wiring between PCM and transmission control module
30%
Failed transmission control module with internal short
20%
Damaged or corroded connector at TCM or PCM
10%
Chafed wiring harness rubbing against chassis ground
Diagnostic Steps
1
Step 1: Inspect MIL bulb and circuit for shorts, test lamp operation with scan tool MIL command
2
Step 2: Check for DTCs in transmission control module and verify TCM communication with scan tool
3
Step 3: Disconnect TCM connector and measure resistance to ground on MIL circuit wire (should be high resistance)
4
Step 4: Trace wiring harness between PCM and TCM for damage, chafing, or pinch points
5
Step 5: Test TCM power supply and ground circuits for proper voltage and continuity
Estimated Repair Cost
$100 - $900
Parts + labor, varies by vehicle and location
The PCM has detected a short circuit to ground in the malfunction indicator lamp (MIL) control circuit that communicates with the transmission control module. This prevents proper MIL operation and module communication.
The most common cause of P1611 (MIL Call-up Circ./Transm.Contr.Module Short to Ground) is: Short to ground in wiring between PCM and transmission control module
Typical repair costs for P1611 range from $100 to $900, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Check engine light may not illuminate when faults occur, preventing driver awareness of problems. Vehicle typically safe to drive but monitoring system compromised.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P1611 to identify the root cause.
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Quick Info
Category
Powertrain
System
Malfunction Indicator Lamp / Module Communication
Difficulty
Type
Manufacturer
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