Pulsar 180 UG4 Headlight Auto Off Problem

[srikantchauhan]

I have pulsar 180 ug4, 2011 model.
For the last few days I am experiencing a strange problem with my bike. After turning on headlight, it turns off after few seconds.

I went to mechanic, he told me that it is sensor problem, it has to be replaced. Price quoted for sensor was Rs 1050.

I am clueless about the problem, I googled about it but didn't find any solution. One more guy seems to be having the same problem. He posted is here

https://www.youtube.com/watch?v=Lyb8gZT1J8c
Pulsar 180UG4 Headlight problems! Aargh! | India Travel Forum, BCMTouring

Did anyone faced the same problem, if yes, how it was fixed.

 

[pravin1987]

it's a part of feature not to allow the battery to drain when head light is turned on without the bike running.

if the head light turns off even with the bike running, battery might be in it's dead stage

 

[srikantchauhan]

No battery is new, just changed 1 month back.
I didn't notice but problem might have started after changing the battery.

it's a part of feature not to allow the battery to drain when head light is turned on without the bike running.

if the head light turns off even with the bike running, battery might be in it's dead stage

 

[bhvm]

Are you using an HID lamp?
The symptoms are of an EOL (end of life) HID lamp that cannot sustain arc due to electrode gap.

 

[srikantchauhan]

No, I didn't change the headlamp, it is stock lamp.

Are you using an HID lamp?
The symptoms are of an EOL (end of life) HID lamp that cannot sustain arc due to electrode gap.

 

[bhvm]

did you visit the authorised Service center?

 

[srikantchauhan]

No not yet, want to know the root cause and if possible fix it myself.

Two more problems
1. Speed in speedometer keep fluctuating e.g it become 0 or 3, 15 randomly.
3. Bars in fuel gauge keep on moving up and down e.g showing 4 bars at the moment, will show 5 after few mins or if turn off ignition and then turn on again will show 6.

All these problems seems to be related to malfunctioning of some electrical component.

did you visit the authorised Service center?

 

[bhvm]

yea this is Electrical malfunction. could be moisture, or rat chewing on wires or something else.

I suggest you visit the service center & get their opinion first. fixing issues oneself is only the last resorts.

 

[Ilangop]

I have pulsar 180 ug4, 2011 model.
For the last few days I am experiencing a strange problem with my bike. After turning on headlight, it turns off after few seconds.

I went to mechanic, he told me that it is sensor problem, it has to be replaced. Price quoted for sensor was Rs 1050.

Was the engine running while this happened?
As the UG4 P180 and P220 have full DC (battery driven) lighting system, this feature is provided to turn off the light when engine is not running still key is kept in the On position. The feature is controlled by the Body Control Module (BCM) a black coloured box sitting just behind the headlamp. If all functions like auto off blinkers, reset after 3 missed cranks, etc. are functional then the only possibility is that the engine rpm signal is not reaching the BCM from the CDI box. Is the engine rpm fluctuating or dead? Could be due to a rat bite or some sharp body part trying to cut through the wire.
See the attached picture. Confirm if the white / Red wire from CDI to BCM is continuous or broken somewhere in between. If you don't have a multimeter, run a wire parallel to these 2 points and see if the headlight function is regained.

We will come to the speedo problem after sorting the issues with BCM

-Ilango

 

[amitpshelke]

I think the culprit is BCW unit which might have damaged during run. A high voltage signal might have shoot the BCW unit badly due to which it is malfunctioning. Try to find same unit from any of your friends bike, try to replace it and see it work fine.

Else go to expert mechanic to get this sort out. BCW is not a repairable unit.

 

[srikantchauhan]

As Ilangop and amitpshelke guessed it correctly, this problem was because of faulty BCU(Body Control Unit). Got it replaced, working absolutely fine.

Thanks a ton to everyone who gave their time to post a reply on this thread.

It solved two problems
1. Headlight auto turn off after few seconds
2. Turn Indicators were not working, it was thinking that LH switch went kaput, but working fine now.

Speedometer problem was because of vehicle speedos sensor(cable that connects to meter), got it replaced along with case meter housing.

Official part number for the components are
1. BCU - JC201016
2. Vehicle Speedos Sensor - JC201043
3. Case Meter Housing - JC151020


Attaching some pics for the reference.

New BCU Box

Old BCU

Case Meter Housing

Fual Gauge problem is yet to be sorted out, but this is not a priority, so I am ok if it take time to be resolved. Anybody has any pointers about it?

 

[Tarun Bharani]

Was the engine running while this happened?
As the UG4 P180 and P220 have full DC (battery driven) lighting system, this feature is provided to turn off the light when engine is not running still key is kept in the On position. The feature is controlled by the Body Control Module (BCM) a black coloured box sitting just behind the headlamp. If all functions like auto off blinkers, reset after 3 missed cranks, etc. are functional then the only possibility is that the engine rpm signal is not reaching the BCM from the CDI box. Is the engine rpm fluctuating or dead? Could be due to a rat bite or some sharp body part trying to cut through the wire.
See the attached picture. Confirm if the white / Red wire from CDI to BCM is continuous or broken somewhere in between. If you don't have a multimeter, run a wire parallel to these 2 points and see if the headlight function is regained.

We will come to the speedo problem after sorting the issues with BCM

-Ilango

Hello Sir,
I am Exactly Facing the same problem of Headlight Auto Off in Pulsar 150 UG4 , by reading your post in this forum i replaced my BCU unit but still the problem is there, also the negine rpm sgnal is proper.

Please help

 

[Ilangop]

Hello Sir,
I am Exactly Facing the same problem of Headlight Auto Off in Pulsar 150 UG4 , by reading your post in this forum i replaced my BCU unit but still the problem is there, also the negine rpm sgnal is proper.

Please help

Hi Tarun,

How did you confirm that the engine rpm signal is proper?

-Ilango