B1676 on Jaguar: How to Diagnose & Fix
Battery Pack Voltage Out Of Range
1 Jaguar model · 1 documented issue · $200-$1,200 repair
B1676 on Jaguar by model: symptoms, diagnosis and fix
XK owners frequently report flat batteries from parasitic draw when a control module fails to enter sleep mode. Normal quiescent draw should fall to roughly 30-50 mA within about three minutes of lock-up; faulty cars have been measured at 200-220 mA, enough to reach 50% state of charge in under two weeks. The Body Control Module (BCM) is a documented culprit (including cases of burnt board traces/failing capacitors), and the fault is worst on cars driven infrequently.
Common Symptoms
- Flat/dead battery after a few days of sitting
- Quiescent draw well above ~50 mA
- Intermittent electrical gremlins, worse in winter
- Modules waking after lock / car not sleeping
How to Fix
Measure quiescent current after the car has gone to sleep, then use the fuse-pull method (allowing re-sleep between pulls) to isolate the circuit/module. Repair or replace the offending module (commonly the BCM) or the stuck accessory. Keep the car on a smart maintainer if it sits, and verify the battery itself is healthy before chasing the drain.
Sources for this issue (2)
B1676 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does B1676 mean on a Jaguar?
B1676 stands for "Battery Pack Voltage Out Of Range." A control module reports that its supply voltage has left the acceptable operating window. Ford's published criterion is battery voltage below roughly 9.7 volts for more than about 210 ms with vehicle speed above 20 km/h (12 mph), or above roughly 18 volts at any time. It is a supply-quality code that many Ford-family modules can set, and it commonly appears as a companion code when a weak or degraded 12V battery causes voltage sag during cranking or during auto start-stop restarts. Because the code is set by whichever module saw the sag, it must be read together with that module's identity — when it is stored by the ABS module on Ford-family vehicles it is frequently caused by an internal module fault rather than the battery itself. On Jaguar it is documented across 1 model: XK.
What are the most common causes of B1676?
The most common causes of B1676 are: Weak, sulfated or end-of-life 12V battery (voltage sag under load or during auto-restart), Failing alternator / charging system, or overcharging producing high-voltage spikes, Corroded, loose or high-resistance battery terminals and ground straps, Blown module fuse, open or shorted module power/ground harness, Poor connector contact at the module; internal ABS module failure on some applications. The specific cause varies by vehicle.
How much does it cost to fix B1676 on a Jaguar?
Published repair estimates on Jaguar range from $200 to $1,200 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for B1676 on a different make?
View B1676 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.