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Experts please help: voltage drop when compressor kicks in

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hammerdin
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Experts please help: voltage drop when compressor kicks in

Post by hammerdin » Thu Aug 15, 2013 10:53 pm

need some experts to advice.

last week was 14V, compressor kicks in drops to 13.6-13.7V

last Saturday:
1. Start engine, no aircon - Voltage 14V. (rpm 1.5k)
2. car stationary, car after warm up, switch on aircon drop to 13V and slowly climb back to 14V (rpm 850)
3. Car still stationary, compressor kicks in, drop to 13V and slowly climb to 14V (rpm 850)
4. Car still stationary, Off aircon, remains steady at 14V (rpm 850)
5. car stationary, switch on aircon and lights, drop to 13 V, slowly climb up (rpm 850)
6. car stationary, compressor kicks in, head lights flicker, drop to 13 V, slowly climb up (rpm 850)
7. car moving same as above, when compressor kicks in, will drop to 13.2V and climb again back to 14V

No mod or anything done over last week before problem comes out. Have checked aircon compressor, not spoilt. Have change battery, still same problem exist.

Because this had deviated from the orginal and I want to rectify the problem before one morning wake up, want to send kids to school and wife to work, car cannot start...

did anyone has this problem before? what could be spoilt? alternator??

Can anyone help?

cl7teckie
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Post by cl7teckie » Sat Aug 17, 2013 9:46 am

hammerdin, u missed the most important info. What car. I believe u driving a accord.

And in this case, there is nothing wrong. In CL7/CM5/CU2, the ECU will switch of the alternator for a while, before kicking in the Air-con clutch. It is part of the "programme'.
Pls dont ask me for wkshop, as I know none...I only know it is safer and faster to fix cars on my own.

hammerdin
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Post by hammerdin » Sun Aug 18, 2013 10:46 pm

thanks bro teckie.... fd2r....

I guess it's normal then...

hammerdin
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Post by hammerdin » Sun Aug 25, 2013 12:44 am

now with lights on and aircon on, voltage drops to 12.6V when compressor kicks in... is this normal?

cl7teckie
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Post by cl7teckie » Sun Aug 25, 2013 10:14 am

When ur compressor kicks in....the alterator is TOTALL shutoff. And a fully charged lead-acid battery is 12.6v

Pls go do more research before asking...pianz.
Pls dont ask me for wkshop, as I know none...I only know it is safer and faster to fix cars on my own.

hammerdin
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Post by hammerdin » Sat Aug 31, 2013 1:02 am

now drop to 12.3V, and lights flicker. is this normal then?

Note: battery just changed as well.

holysniper
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Post by holysniper » Wed Sep 04, 2013 6:12 pm

go have ur alternator tested by a workshop...

are ur foglights on?

hammerdin
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Post by hammerdin » Fri Sep 06, 2013 11:00 pm

holysniper wrote:go have ur alternator tested by a workshop...

are ur foglights on?
bro, car no foglights, no ICE.

EQK
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Post by EQK » Sun Sep 08, 2013 9:53 pm

Voltage reading sounds normal leh. I think u worry too much. U should only worry about battery when voltage drops below 12v. Normal range of battery voltage is between 12v-15v, depending what u have that the battery is powering and what is on.

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