🔧 Common Fault Codes We See (and Fix):
- P7087 variants (e.g., -87, -71, -11, -29): Invalid data, range sensor errors, or shift control circuit faults in the GSM.
- U0001: High-speed CAN bus communication loss, often triggered by the GSM dropping offline.
- P0850 & P1707: Park/neutral switch or transfer case neutral issues in the TCM, cascading from GSM failure.
- Airbag codes like B1026 or B1109 may appear unrelated but can be inspected during our full harness check.
Key Insights for JLR Vehicles
🔍 GSM Fault Confirmation
The cluster of P7087 variants across GSM-related modules is a classic indicator of a failing Gear Shift Module in JLR systems. This often stems from internal electronics degradation, water ingress (common in Land Rovers), or mechanical wear in the rotary selector. The U0001 CAN bus code is frequently a symptom of the GSM "going dark" on the network, pulling down other modules.
🔗 Interconnected Issues
The TCM codes (P0850, P1707) are downstream effects—the GSM provides essential PNP/neutral data to the TCM. Airbag codes (B10xx) appear unrelated but warrant checking during harness inspection.
🚗 Common in Models
Seen frequently in 2010–2020 Range Rover/Discovery (L322/L405), Jaguar XF/XJ. Check for TSBs like SSM 48158 (GSM replacement) or LTB00462 (wiring harness updates).
Compatible Vehicle Models
Range Rover Evoque
LR4
Discovery
Discovery Sport
Range Rover
Range Rover Velar
Part Numbers We Service
LR072305 LR072650 LR060305 LR090489 LR068891 LR066522 LR052082 LR024731
Common Symptoms We Fix
- Shift module knob is stuck in gear and does not move at all
- Vehicle stuck in neutral, shifter rises and falls but blinks neutral
- Vehicle stuck in neutral and shifter knob won't go up or down
- Shifter will not raise or go in gear
- Shifter will rise, but not able to be turned into gear
- Shifter dial stuck in "D"
Detailed Fault Code Reference
| Module | Fault Code | Description | Symptoms |
|---|---|---|---|
| High Speed Bus | U0001-000001 | High Speed CAN Communication Bus - Loss of communication | Multiple module dropouts, no-start, erratic dash lights |
| IPC Cluster | P7087-87 | GSM Invalid Data Received | Gear selector not responding, "Transmission Fault" warning, limp mode |
| IPC GSM | P7087-71 | GSM Range Position Sensor Circuit | Unable to shift out of park, no-start |
| GSM Shift Control | P7087-11 | GSM Shift Control Circuit Low/Open | Rotary dial stuck, grinding noises on shift attempt |
| GSM | P7087-29 | GSM Performance/Intermittent Signal | Delayed/inconsistent shifting, intermittent "park" engagement |
| TCM | P0850-50 | Park/Neutral Position Switch Input Circuit | Engine cranks but won't start, stuck in park |
| TCM/BCM | P1707-72 | Transfer Case Neutral Indicator Circuit Intermittent | 4WD issues, inability to shift to neutral, warning lights |
| GSM | P176C-11 | Transmission Range Selector - circuit short to ground | Selector lock issues, unable to change gears |
