Of Flickering Lights, Air Conditioning Faults and Warning Lights
10-06-2017, 05:43 PM
#1
Rennlist Member
Thread Starter
Of Flickering Lights, Air Conditioning Faults and Warning Lights
Posting this for future reference should anyone have one or more of these problems.
Had flickering lights (interior and exterior) plus the occasional warning lights flashing briefly since around the beginning of the year. Thought it was a ground problem and worked all the ground terminals to no avail. Then, on a club drive early this summer, the AC all but quit cooling on the way home after lunch, warning lights lit briefly but often (mitigated by turning on headlights(?)) and servo flaps occasionally would go crazy. Couldn't find the problems after noodling with various things over the course of the next few days (CCU, ground terminals, servo flap positions, A/C charge, various fuses/relays, condensor, etc), then shelved driving/working on it for the summer.
Renewed the effort this last weekend when inspection came due. Unplugged the battery tender and headed to the local inspection station on Saturday late afternoon, where the car passed without issue. Left it off the battery tender overnight as I planned on having the alternator checked while buying a new battery ground wire at the local Auto Zone the next morning. Jumped in the car on Sunday morning and battery was dead. 10.4 volts on a two year old Bosch wet cell battery. Maybe a dead or shorted cell.
Pep Boys made good on the battery- 100% replacement under warranty, plus allowed an upgrade to a Bosch AGM for twenty bucks! Slipped the new battery in place and all problems magically went away. Apparently, the battery tender masked the battery problem as voltages were previously correct. Might also had been that the battery was progessively limping until the problem ultimately manifested itself. Or, maybe a combination of the two.
In hindsight, the battery was no doubt causing the flickering lights, warning light display and servo flap craziness. I suspect that, when they weren't flopping around, the servo flaps (and/or the CCU) weren't getting quite the right current to position the flaps correctly, which may have caused the system to introduce heated air from the engine.
Had flickering lights (interior and exterior) plus the occasional warning lights flashing briefly since around the beginning of the year. Thought it was a ground problem and worked all the ground terminals to no avail. Then, on a club drive early this summer, the AC all but quit cooling on the way home after lunch, warning lights lit briefly but often (mitigated by turning on headlights(?)) and servo flaps occasionally would go crazy. Couldn't find the problems after noodling with various things over the course of the next few days (CCU, ground terminals, servo flap positions, A/C charge, various fuses/relays, condensor, etc), then shelved driving/working on it for the summer.
Renewed the effort this last weekend when inspection came due. Unplugged the battery tender and headed to the local inspection station on Saturday late afternoon, where the car passed without issue. Left it off the battery tender overnight as I planned on having the alternator checked while buying a new battery ground wire at the local Auto Zone the next morning. Jumped in the car on Sunday morning and battery was dead. 10.4 volts on a two year old Bosch wet cell battery. Maybe a dead or shorted cell.
Pep Boys made good on the battery- 100% replacement under warranty, plus allowed an upgrade to a Bosch AGM for twenty bucks! Slipped the new battery in place and all problems magically went away. Apparently, the battery tender masked the battery problem as voltages were previously correct. Might also had been that the battery was progessively limping until the problem ultimately manifested itself. Or, maybe a combination of the two.
In hindsight, the battery was no doubt causing the flickering lights, warning light display and servo flap craziness. I suspect that, when they weren't flopping around, the servo flaps (and/or the CCU) weren't getting quite the right current to position the flaps correctly, which may have caused the system to introduce heated air from the engine.
10-08-2017, 09:35 AM
#2
RL Community Team
Rennlist Member
Rennlist Member
I would do a quick check of the running voltage between 13.5 & 14.5. A fresh battery with a marginal alternator will run great until it slowly runs down due to inadequate charging.
10-08-2017, 03:04 PM
#3
Rennlist Member
Thread Starter
Yes, I neglected to mention that I had the alternator checked out immediately after installing the battery. 14.2 volts charging, plus diodes and voltage regulator are good. Drove it about 100 miles yesterday with no issues.
10-09-2017, 11:27 PM
#4
Interesting. Just the other evening I noticed all the warning lights in the oil temp/press gauge "glow" very briefly and dimly (but barely noticeable). It did this a couple of times, not sure I would have seen it during the daytime. I have a little voltmeter in the cigarette lighter and the alternator is charging normally.
Battery is four years old. I usually get much more than four years out of a battery but I'll have to look into this one.
Thanks for posting.
Battery is four years old. I usually get much more than four years out of a battery but I'll have to look into this one.
Thanks for posting.