Hi there – check fuses first, but it sounds like you might have a problem with your digital dash, and possibly a wiring issue that is draining your battery overnight. The lack of gauge function is is a high failure rate circuit board issue, but there are rebuilder service companies out there that specialize in this work. The battery drain issue maybe be a different problem, but can be tracked down as well. This problem can be diagnosed by connecting an ammeter to the positive (red) battery cable, observe the current drain (likely less than 1 amp), then, one at a time, remove each fuse, check to see if the current drain has dropped to near 0, then reinsert the fuse. This process should identify the faulty circuit in most cases. The specific components on that circuit can then be checked for current drain problems. A professional mechanic, like YourMechanic, can come to your location, and perform this procedure for you, and replace/repair the failing component.
How to Identify and Fix Common car Problems ?
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The most common causes of a speedometer that stopped working include are a faulty speed sensor, a broken gear on the speedometer, damaged wiring, or a faulty engine control unit.
A speedometer that is not working properly can be caused by a few different things. The most common issue is a problem with the gauge cluster itself, which could be caused by a faulty gauge motor or stepper motor. Another possibility is that the circuit board has become damaged and needs to be repaired or replaced.
Gauges twitching after attempting to start the engine is usually a sign that the battery doesn`t have the capacity to crank the engine; this is either due to a bad battery or a bad alternator that is failing to keep the battery charged.
Dashboard lights can become non-functional for various reasons. In case, the dimmer switch on the dashboard is turned down or off, the dashboard lights will not show. Also, a blown fuse or a bad lightbulb can cause the non-functionality of these dashboard lights.
While you are driving, if you notice the needle on the speedometer jumps erratically from one number to another, the speedometer cable is most likely damaged or the sensors on the driveshaft are not accurately sending the signal through the cable.
Your speedometer is directly linked to the speed sensor — meaning if anything goes wrong with the vehicle speed sensor, it`ll lead to a speedometer failure. Whether you have hall effect or digital speed sensors, here are some signs of a bad sensor that may accompany your erratic speedometer needle: Transmission issues.
A common problem for this malfunction is when the car owner recently replaced the battery, or perhaps jump-stared their vehicle, which in both cases could have caused an electrical spike that made the speedometer go berserk.
The problem could be the hairspring inside the speedometer. Hairspring holds the `speed cup` inside mechanical speedometers and if they break or become loose, the pointer can jump abruptly on the dial. I will advise to swap your speedometer with a known good one to see if the same cable performs fine with it.
Is It The Battery? Battery problems can also cause issues with the instrument cluster operation. Flickering lights or erratic gauges could be a sign of a weak battery. Sometimes various modules within your car (including the cluster) causing a battery drain, even when the car is turned off.
An early warning sign that your alternator is going bad could be dim, flickering lights. This symptom could show up on any or all of your dashboard lights, reading lights, headlights or other lights. The alternator is supposed to provide the electricity for your car`s lights.
The instrument cluster fuse, also known as the dashboard fuse, powers the gauges and displays on your vehicle`s dashboard. This includes the speedometer, tachometer, fuel gauge, and temperature gauge.
The output speed sensor is also known as the vehicle speed sensor in a vehicle. It transmits a signal to the transmission control unit, informing it of the vehicle`s speed. Failure of the speed sensor is a common reason for taking the car to the mechanic.
The vehicle may lose vehicle speed signal, which can affect speedometer operation and transmission shift quality. Most often the vehicle speed sensor is faulty, however, at times, the driven gear inside the transmission is at fault.
Underperforming Electrical Systems
You might notice your car`s power windows rolling slower, the speedometer acting up, or the stereo system`s output getting softer due to alternator trouble. These are tell-tale signs of an issue with your vehicle`s electrical system.
In speedometer controllers of this type that use a detection signal from a vehicle speed sensor, the detection signal from the vehicle speed sensor is transmitted through a powertrain control module (hereinafter referred to as “PCM”).
Typically the speed sensor mounts on the transmission and gets its signal from a toothed gear inside the transmission housing. The sensor has an electric current running and a magnetic tip that sits very close to the teeth on the gear.
Faulty Fuse/Bad Wiring: In very wet conditions, it is possible for exposed wires to get wet and short out, causing a fuse to blow. When the fuse for your speedometer stops working, it can cause the speedometer to drop to zero.
Transmission Range Sensor (TR)/ Transmission Position Sensor The PCM uses this information to control which gears of the transmission to enable or disable. When the TR sensor fails it can cause wrong gear starts, no upshifts, or what feels like a falling-out-of-gear condition.
If you use the wrong size battery, this could cause changes in the flow of electrical currents, resulting in power surges that can damage the onboard computers or other components.
When the battery current sensor fails, the vehicle will not charge correctly, leading to a DTC or a dead battery. Common signs of failure include: Irregular charging rates. Low battery voltage.
Gauges flickering and the car won`t start usually indicates a power problem. Usually, a battery problem comes with clicking sounds. To determine the source, call a mobile mechanic and ask for help conducting a battery inspection.
Some gauges, like the speedometer, odometer, and tachometer, use small gears. These small gears can wear out over time, leading to mechanical failure of the gauge(s). A bad alternator can cause voltage spikes.
Parasitic drain
A parasitic drain refers to when your car`s battery continues to drain even after the car`s parked, and the amount of drainage is much higher than normal. Usually, it`s a faulty accessory in the car causing the drain – for example, a sensor or interior light doesn`t switch off automatically.
If the instrument cluster fails while driving, then this will often cause the engine to cut out. If failure happens while attempting to start the vehicle then it will prevent the engine from starting.