Question about 2003 BMW Z4

2 Answers

Does low voltage in ignition have to do with a weak battery

Does low voltage have to do with a weak battery

Posted by on

2 Answers

  • Level 1:

    An expert who has achieved level 1.

    Corporal:

    An expert that hasĀ over 10 points.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 11 Answers

It can do. It depends on where you are measuring the voltage. When the starter motor is turning the engine over it draws considerable current say 200 amps on a cold morning. If the battery is failing then the voltage may have dropped so low as to cause the ignition to not operate and the engine will also be turning over slower than normal. A flat battery due to leaving the interior light on overnight just requires an overnight charge. Some unscrupulous shops will just sell you a new battery.
The battery is composed of 6 cells, each of 2 volts. When a battery is old, a single cell can fail and itself become a high resistance. This resistance prevents the high current required by the starter motor from flowing yet the battery may actually measure nearly 12 volts. A high current test of the battery by an auto shop using a high current discharger with voltmeter will give a good check. Simply measuring the battery using a volt meter will tell you almost nothing, as a poor battery will still measure nearly 12 volts. A quick test at home is as follows. Turn on headlights. Get a friend to watch them as you turn the engine over by starter motor. If the lights go dim then the battery is faulty (or you have a very bad connection to the battery) Another simple check of the alternator is; with the engine idleing turn on all lights, heated rear screen etc and slowly increase the engine rev's. The lights should slightly increase in brightness as the alternator starts to charge the battery. (This check will not be visble with discharge type headlights)

Posted on Apr 01, 2014

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    MVP:

    An expert that gotĀ 5 achievements.

    Scholar:

    An expert who has written 20 answers of more than 400 characters.

    Hot-Shot:

    An expert who has answered 20 questions.

  • Expert
  • 63 Answers

If the voltage drops more than is normal during the ignition cycle, this can be caused by a weak/old battery (Insufficient crank amperage) or by problems with the starter motor. Most auto part shops will test your electrical system for you for free and can determine whether the battery is having problems, the alternator is failing, or the starter motor is faulty.

Posted on Mar 28, 2014

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

2006 Ford 500. Good battery power. clicks when ignition is turned( sounds like low voltage ) car died while driving. Won't restart. Fuel pump??


You might think the battery is good,but it might be weak or alternator going out. Check battery connections also. don-ohio

Feb 13, 2017 | Ford Cars & Trucks

1 Answer

What does the code c0277 mean on a 1999 isuzu rodeo


C0277 is low ignition voltage
i dont have the book to cover that error.
but is ether
1: battery was low cranking, was it? (heard starter run slow?)
2; weak spark. get a tuneup yet>

why not reset the PCM, (push reset on the scan tool and)
see if it comes back.
that be first first.

Nov 21, 2016 | 1999 Isuzu Rodeo

1 Answer

Why a weak spark 1987 dodge 5.9 v8


this can be caused by a weak battery check battery and charging system to verify a good working system. it could also be a weak coil not being able to supply enough output voltage for the ignition system. you don`t say if its weak coming out of the coil or at the plugs. if spark is weak at the plugs it could be a bad cap/rotor, ignition wires. it could also be an ignition module problem or pick-up coil in the distributor.

Aug 25, 2014 | Cars & Trucks

1 Answer

Missing, spitting, backfiring


Hello Chris,

This sounds like you have a timing issue. Check you crank angle and camshaft position sensors for correct signals, also check that the physical timing has not gone out.

Could also be a weak mixture, so check your fuel pressure & fuel flow. If the colours of the pre cat lambda sensor are white/white/black/grey then you can use the voltage output from the sensor to determine the state of the air/fuel ratio. The sensor works in the range of 150mV to 950mV (so 0.150 volt to 0.950 volt), when a weak fuel condition exists (lots of exhaust oxygen) the sensor will out put a low voltage. The sensor when on the correct exhaust conditions constantly switches high - low - high - low etc etc.... if low and staying low you have a weak fuel mixture. You can prove it by watching the sensor voltage and spraying some start fluid in to the intake, which will make the voltage rise. NB: be very careful (or don't do it) if you have back firing, as a back fire through the intake will ignite your start fluid!!!

Aug 17, 2013 | 2000 Dodge Durango

1 Answer

Code 12 1995 dodge spirit 2.5 battery and PCM NOT disconnected. where does the pin 3 on PCM gets its battery suppy voltage from


Has the battery been disconnected or been low on charge in the last 50 ignition cycles?

Code 12 means that battery power has been disconnected within the last 50 ignition cycles. it does not mean there is no battery power to the computer

Pin 3 should be a red/white wire that is the constat power supply to the PCM. It is protected by a fusible link located neer the drivers side strut tower. If that link was bad the car would not start or run as it also supplieds power to the asd relay, fuel pump relay, and the ssd relay.

I would put money on the the problem being igntion (plugs wires cap rotor), compression (low cylinder compression usually cylinders 2 and 3), lack of fuel delivery (low fuel pressure, a weak or dirty injector), timin (timing belt jumped, worn distributor, look exciter ring), or possibly a plugged catalytic converter.

I would check compression first especially cylinders 2 and 3. It was pretty common for the head gasket to fail in between these two cylinders.

Feb 24, 2012 | 1995 Dodge Spirit

1 Answer

Won;t crank


Hi, if the car engine fails to crank, there is a fault in one of the components in the battery/ignition/starter circuit. Low battery (Check battery voltage, recharge if low, or jump start with another vehicle or battery charger). Bad starter relay/solenoid (Check for voltage at relay, if relay has voltage but there is no "click" when key is turned to start, replace relay). Bad ignition switch (Check to see if voltage reaches starter relay/solenoid when turn to start. If not, check for open P/N switch and brake or clutch pedal switch. Replace ignition switch if defective).

May 26, 2011 | 1994 Dodge Stealth

2 Answers

1997 Chevrolet 1500 no start


is the fuel spraying into the cylinders? pull a plug and see if they have fuel on them.....If not you have a problem at the injectors if there is pressure on the rails. If fuel is present you aren't firing strong enough to ignite the fuel. pull a plug and put the wire on it and touch it to a ground and check to see if it is a good blue spark or a weak white or yellow spark...If no spark check for dead plugs or distributor module,

Feb 03, 2010 | 1997 Chevrolet K1500

1 Answer

Can a weak battery cause a BMW to misfire?


hello, if the vehicle ran with cable off one would ASUME alternator is ok! however, i bad diode in the aletnator would allow it to charge yet have a massive voltage draw as well, almost all of todays parts stores will do a free starting and charging test for you! ......ps a large voltage drop would rob your ignition of voltage causing your miss!.good luck, marty

Jun 07, 2009 | 1985 BMW 3 Series

2 Answers

Weak spark + 1988 ford bronco


check the voltage of the b+ terminal of the ignition coil (primary side) with a cheap multimeter while cranking. low voltage to the primary will cause low voltage on the secondary. also recheck all ground paths from the ignition module. ensure good connection from coil to module. note: new parts are not "known good parts" until it runs.--> IG.MOD.

Dec 17, 2008 | 1994 Ford Bronco

Not finding what you are looking for?
2003 BMW Z4 Logo

106 people viewed this question

Ask a Question

Usually answered in minutes!

Top BMW Experts

Frankie B

Level 2 Expert

65 Answers

Fred Sops

Level 2 Expert

272 Answers

Doberman

Level 2 Expert

254 Answers

Are you a BMW Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...