All of my current cars lights dim when I turn on the rear defroster, the idle comes up if I turn on the front defroster (AC). If the idle is lower than normal due to whatever other issue is going on, that would make it more pronounced.
Lights Dimming and Rough Idle
- Thread starter BrandonVA
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Originally Posted By: Pop_Rivit
Originally Posted By: Nick1994
Sounds pretty normal, my 97' Camry did this at idle and even the dash clock would dim at idle LOL until I revved it or drove off from the light.
None of my vehicles lights dim at idle, nor do any of my vehicles exhibit a rough idle. I would disagree that it's normal.
On the other hand, it's not uncommon. Many vehicles do this when under a heavy electrical load. Easiest way to see it is at night- headlights on, blower on high and rear defrost on, all at idle. Then rev the engine gently- you see the lights brighten and the pitch of the blower change. Also, sometimes the load on the alternator will make some smaller engines struggle some, causing a slightly rough idle. The vast majority of the motoring public will never notice this.
Originally Posted By: Nick1994
Sounds pretty normal, my 97' Camry did this at idle and even the dash clock would dim at idle LOL until I revved it or drove off from the light.
None of my vehicles lights dim at idle, nor do any of my vehicles exhibit a rough idle. I would disagree that it's normal.
On the other hand, it's not uncommon. Many vehicles do this when under a heavy electrical load. Easiest way to see it is at night- headlights on, blower on high and rear defrost on, all at idle. Then rev the engine gently- you see the lights brighten and the pitch of the blower change. Also, sometimes the load on the alternator will make some smaller engines struggle some, causing a slightly rough idle. The vast majority of the motoring public will never notice this.
If the Corolla grounds are body grounds this is the problem. Most Asian cars I've seen us this style of grounding. As time goes on the body grounds start to corrode and the resistance increases.
Find the main ground coming off the battery and use a heavy same sized wire to go to the engine block. This should solve the problem and make the engine spin faster when starting.
14V when running is great. You can get the cheap plug into the lighter voltage displays too . Under $5.
Find the main ground coming off the battery and use a heavy same sized wire to go to the engine block. This should solve the problem and make the engine spin faster when starting.
14V when running is great. You can get the cheap plug into the lighter voltage displays too . Under $5.
I did some research before I bought a 12v outlet meter and I got the INNOVA 3721 the cheaper ones don't update fast enough to give accurate results but the innova does.
I noticed my voltage drops bad when I have the rear defroster on at idle only and comes back up quickly as soon as it goes a little above idle. Normally it's around 14.4-14.8v all the time but it drops to 12.9v when rear defroster is on at idle.
I need to check my grounds too.
I noticed my voltage drops bad when I have the rear defroster on at idle only and comes back up quickly as soon as it goes a little above idle. Normally it's around 14.4-14.8v all the time but it drops to 12.9v when rear defroster is on at idle.
I need to check my grounds too.
Originally Posted By: SHOZ
If the Corolla grounds are body grounds this is the problem. Most Asian cars I've seen us this style of grounding. As time goes on the body grounds start to corrode and the resistance increases.
Find the main ground coming off the battery and use a heavy same sized wire to go to the engine block. This should solve the problem and make the engine spin faster when starting.
14V when running is great. You can get the cheap plug into the lighter voltage displays too . Under $5.
I have couple them. Camry has two outlets next to each other. There is at least 0.2 volt difference between the two display. And yes, I swapped them and the difference moves with the display. One of them is lazy to update its display. Those things are not accurate and should only be used for getting a ballpark numbers
If the Corolla grounds are body grounds this is the problem. Most Asian cars I've seen us this style of grounding. As time goes on the body grounds start to corrode and the resistance increases.
Find the main ground coming off the battery and use a heavy same sized wire to go to the engine block. This should solve the problem and make the engine spin faster when starting.
14V when running is great. You can get the cheap plug into the lighter voltage displays too . Under $5.
I have couple them. Camry has two outlets next to each other. There is at least 0.2 volt difference between the two display. And yes, I swapped them and the difference moves with the display. One of them is lazy to update its display. Those things are not accurate and should only be used for getting a ballpark numbers
Originally Posted By: Vikas
Originally Posted By: SHOZ
If the Corolla grounds are body grounds this is the problem. Most Asian cars I've seen us this style of grounding. As time goes on the body grounds start to corrode and the resistance increases.
Find the main ground coming off the battery and use a heavy same sized wire to go to the engine block. This should solve the problem and make the engine spin faster when starting.
14V when running is great. You can get the cheap plug into the lighter voltage displays too . Under $5.
I have couple them. Camry has two outlets next to each other. There is at least 0.2 volt difference between the two display. And yes, I swapped them and the difference moves with the display. One of them is lazy to update its display. Those things are not accurate and should only be used for getting a ballpark numbers
LOL .2v is less than 2% error. What more do you really need? If the alternator is working then it will read above 13.5, if not then it's really easy to see if you're running on battery voltage.
Many cars today have ECU controlled alternators that fluctuate the voltage all the time.
Originally Posted By: SHOZ
If the Corolla grounds are body grounds this is the problem. Most Asian cars I've seen us this style of grounding. As time goes on the body grounds start to corrode and the resistance increases.
Find the main ground coming off the battery and use a heavy same sized wire to go to the engine block. This should solve the problem and make the engine spin faster when starting.
14V when running is great. You can get the cheap plug into the lighter voltage displays too . Under $5.
I have couple them. Camry has two outlets next to each other. There is at least 0.2 volt difference between the two display. And yes, I swapped them and the difference moves with the display. One of them is lazy to update its display. Those things are not accurate and should only be used for getting a ballpark numbers
LOL .2v is less than 2% error. What more do you really need? If the alternator is working then it will read above 13.5, if not then it's really easy to see if you're running on battery voltage.
Many cars today have ECU controlled alternators that fluctuate the voltage all the time.
One of the weekend, I am going to borrow couple of Flukes from the work and perform the same experiment. I should have added my PowerProbe 3 to the mix along with couple of more HF freebies in the mix. Surely, one of them has to be giving me the correct reading!
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