I have a 2000 VW Beetle, the blue temperature light is on all the time, it is kangerooing with no acceleration when cold, nothing shows up on the code reader any ideas Laura

The blue temp light indicates that the engine is cold and has not yet come up to optimal running temperature. When the car shut off, were there any warning lights on? It could have overheated, the red temp light would have been on. Is the check engine light on at all?

First time you might check the thermostat operating.

Heed of antifreeze coolant temperature!!!

The thermostat location for 2000 VW Beetle 2.0L is on back of the alternator at the bottom side of the bracket.

IMPORTANT NOTE: It is NOT necessary to replace the alternator if you want to change the thermostat !!!

Thermostat checking:
1. Cold engine. Start up the engine and watch of the water temp indicator. After first value 60 Celsius Degree you still warm up the engine until the lifter (pointer) reach 80 C deg. (second mark after 60 C deg.). At this time you let engine running at idle speed and check with your hand the thermostat plastic housing and hose temperature in bottom left side of the engine. Heed of alternator driving belt and ventilator fan !!!
2. If the thermostat is good the hose must be cold until the water temp indicator reach almost 90 C deg.
3. The thermostat opening temperature is 87 C deg.
4. If the hose is already warm the thermostat is out of order.

Thermostat location, Part number: 050 121 113 C, in german - "Kuehlregle".
Remark: 87 ... 102 Celsius deg.
Price around $35:



Important note: Always replace the thermostat seal, position 7 in the above picture.

the blue light comes on when cold and goes off when engine is hot enough to use full power.if it stays on,the temp sensor is faulty.

16501/P0117 - Engine Coolant Temperature Sensor (G62): Signal too Low Possible Symptoms

• Difficulties with starting a cold engine.
• Starting the engine when engine is warmish or warm, idle rpm immediately is 1200 - 3000 rpm.
• RPM at idle is irregular.
• With all engine temperatures seldom idle rpm will vary between 900 - 1000 rpm.
• With engine warm (90 °C) the engine temperature suddenly drops (70 °C) and slowly comes back to 90 °C.
• Bad acceleration during warming up.
  • Diesel: an indication is extreme long time burning time of the glow indication light.

Possible Causes

• The electrical signal coming from G62 is too low
• Wiring and/or connections faulty (short circuit?)
• Engine Coolant Temperature Sensor (G62) faulty

Possible Solutions

• Check wiring and connections
• Check / Replace Engine Coolant Temperature Sensor (G62)

Special Notes

• In MY 1995-2002 (?) in Europe at VW-cars the G2/G62 had the bad reputation of breaking down often. The default G2/G62 is black and all replacements are green.

Is your check engine light on? Check the throttle body or maybe the accelerator pedal is bad.

maybe coil pac!!!

water level needs topped up do this when cold because water expands when hot. hope this helps?

Not certain, but you may be referring to the blue light that indicates when the water temperature in the cooling system is "cold". It's typically blue when the car first starts, then changes color when the water temperature rises. If the light remains blue the water temperature isn't heating up, and you may want to have the cooling system flushed and checked. Depending upon the cars mileage, it may be time to flush the cooling system anyway.

For general awareness, the outside air temperature sensor is located above the inside mirror.
Try to reset the temperature measurement unit: 1. Switch engine on. 2. Press and hold clock minute (min) and hour (h) buttons simultaneoutly longer than 3 seconds. The display will show new temperature measurement unit. 

its normal if the engine is cold,it should go out once it warms up....