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Preheating control unit defective
The relay controls the pre-glow system for smooth diesel engine starting.
Costs
Every car issue can be caused by different things. Here are the most common ones
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Most Expensive
Moderate costs
Moderate costs
Cheapest case
Discussions
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Details
Probability
Based on the values and symptoms you have entered, a crude estimation of the probability of this problem can be made
HIGH
Typical consequences
If this defect is detected, it may lead to the following problems:
- Turbocharger damage
- Exhaust system damage
- Failure of the exhaust emission test (Failure to pass the exhaust emission test)
Function of glow plugs
In a vehicle, glow control units or pre-glow relays serve to control all glow plugs. They supply the glow plugs with a specific setpoint current during starting, which is defined by the engine control unit. Alternatively, they can also be programmed to supply the glow plugs with current for a previously defined period.
The pre-glow relay is connected to the engine control unit and the glow plugs via wiring, which enables an exchange of information during engine operation. For example, so-called intermediate glowing can be initiated if certain target values, such as exhaust or intake air temperature, are exceeded or undershot.