1987 PORSCHE 944 charging

Right Instrument Cluster
The right instrument cluster combines the oil
pressure gauge with the oil pressure warning
light, the voltmeter with the alternator warning
light as well as the brake fluid warning light.

Oil Pressure Gauge
Engine oil pressure is shown in bars. At 5.000 rpm, with the engine at normal operating temperature (approx. 90°C / 194°F), the pressure should be approx. 4 bar. A slight
drop in oil pressure is normal under certain
operating conditions such as prolonged
highway driving in hot weather.
At idle speed, with the engine oil hot, the oil pressure can sink to 0.5 bar - this does not
indicate any loss of engine performance.
However, if the oil pressure drops suddenly
while you are driving, or if the warning light comes on, pull off the road,
stop the engine
and wait for it to cool down. Check the
engine oil level. If the oil level is normal,
contact the nearest dealer.

Oil Pressure
Warning Light
The oil pressure warning light comes on when the ignition is turned on. It should go out when the engine is started and has reached the
correct oil pressure.
If the oil pressure warning light
does not light up when turning the ignition on, or if it does
not go out after starting the engine, contact
your Porsche dealer immediately.
If the oil pressure warning light comes on
while you are driving, pull off the road and stop the engine .
Check the oil level to make sure you have
enough oil. If oil level is correct and the oil pressure warning light is still on, do not driv
e
the vehicle as severe engine damage may
result. Contact your nearest Porsche dealer
for assistance.
An occasional brief flickering of the oil pressure warning light at idle speed and
normal engine temperature is no cause for
concern if the light goes out upon
acceleration.
The oil pressure warning light is not an
indicator for low engine oil level. To check the
oil level, always use the dipstick.
Make it a habit to have the oil level checked
with every fuel filling.
Voltmeter
The voltmeter shows the overall condition of
the charging system. The needle should
normally stay in the 12-
14 volt range when the engine is running. A temporary drop below 12
volts when starting the engine is normal.
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Alternator Warning Light
The alternator warning light comes on when
the ignition is turned on. It should go out after
the engine is started.
If the alternator warning light does not light
up when turning the ignition on, or if it does
not go out
after starting the engine, there is a malfunction in the electrical system. If this is
the case, contact your Porsche dealer.
WARNING
If the alternator warning light comes on
while you are driving, pull off the road and
stop the engine.
Check whether the Polyrib-belt is slipping or
broken. The Polyrib-belt not only drives the
alternator for battery charging, but also the air
conditioner compressor.
If the light just flickers lightly, the Polyrib bel t
may be loose and is slipping.
The belt should be tightened or replaced
before you continue driving.


Brake Fluid Warning
Light
The brake warning light monitors the hydraulic dual-circuit brake system. It lights up when the ignition is turned on and should go out after
the engine has been started.
If the brake warning light fails to light up when
the ignition is turned on, or if it fails to go out
after the engine is started, there may be a
malfunction in the electrical system. Let your
Porsche dealer locate and correct the
condition promptly.
Should the light come on while driving, the
brake fluid level in the reservoir could be too
low, or one of the dual brake circuits may
have failed. In either case, the brakes will
function but a much longer distance and a far
greater pedal pressure are required to bring
the car to a halt. See "Brakes" for more
details.
Carefully pull off the road and stop. Have
your car towed to the nearest dealer for
repair. Continued operation of a car with
defective brakes is dangerous.
Antilock
The warning light goes on in the event of a
malfunction in the ABS system. The system is
switched off; the normal brake system
remains fully operational. If the light comes
on, take your vehicle to your authorized dealer for service immediately.
Air Bag
See "Air Bag System" for details.

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If it fails to light up, the fuse is defective and
must be replaced. Replace black plastic
cover.
The central electrical system contains plug in
relays for various electrical switching
functions.
Defective relays should be tested and
replaced by an authorized Porsche dealer.
To prevent damage to the electrical system
we recommend having all work - including the
installation of electrical accessories -carried
out by your authorized Porsche dealer. . ,

Fuses and Relays
The individual circuits are protected by fuses
to prevent damage to electrical leads and
components due to short-circuits and
overload.
The fuse box with a black plastic cover is
located on the left side in the engine
compartment directly in front of pivot point for
left windshield washer arm.
The use of the fuses and relays is shown
in a list on the inside of the cover of the
fuses and relays.
Replacing a Fuse
Before replacing a fuse, turn off all
electrical components and the ignition;
remove the key. Replacing a fuse or relay with the
engine running or the ignition on could
cause electrical shock.

A blown fuse indicates an overload in the circuit. When a fuse is blown it is not sufficient
to merely replace it. The cause of the short
circuit or overload must be located. Fuses
should never be patched up with tin foil or
wire as this may cause serious damage
elsewhere in the electrical circuit.
Open snap-on latches and remove plastic
cover.
To find out whether a fuse is serviceable, pull
it out with the plastic pliers specifically
provided for this purpose. Insert the fuse at
the test point on relay (G 3). If the fuse is in
proper condition, the green indicator light will
come on.
Loudspeakers


When installing a radio or booster amplifier,
check that the output is compatible with the
capacity of the loudspeakers supplied with the vehicle.
Rated capacity in Watt (Sinus)
Front Rear
2x10 2x10
HiFi Audio Package 2 x 25 2 x 25
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Battery-12 Volt
The battery is located under the front hood in
the cowl area.
A replacement battery should always have the same rating as the original equipment battery.
Specifications are printed on the battery
housing.
Before work is done on the electrical
system, the battery must be disconnected
to prevent short circuiting. First
disconnect the negative ground wire and
then the positive cable. To reconnect
battery, reverse the procedure.
Disconnecting the battery while the engine is running will damage the alternator. This
also applies to cars equipped with a
battery main switch.
Never drive the car with a disconnected battery as this will damage the alternator. WARNING

Do not lay tools or other metal objects on the battery as they could cause a short
circuit across the battery terminals.
Do not expose the battery to an open flame or electric spark. Hydrogen gas
generated by the battery is explosive.
Do not let battery acid come in contact with skin, eyes, fabric or painted
surfaces.
If you get electrolyte, which is an acid, in your eyes or on skin, immediately rinse
with cold water several minutes and call a doctor. Spilled electrolyte must be rinsed off at once with a solution of water and baking
soda to neutralize the acid and prevent
damage to fabric and metal.
Checking the electrolyte fluid level
The electrolyte fluid level in your battery can
be checked by unscrewing and opening the
filler vent caps of each cell. The fluid level
should meet the indicator mark in each cell. If
necessary, top off with distilled water.
How often water must be added depends on
operating conditions and on the time of year.
Generally, the electrolyte level must be
checked more often in the summer than in the winter, and more often when driving long distances.
Only fill up to mark, otherwise the electrolyte will overflow when the battery is being charged and cause damage.
Battery care
Battery should be securely mounted
Terminals and connections should be kept
clean and properly tightened. Corrosion can
be prevented by coating terminals and
connections with petroleum jelly or silicone
spray
Vent caps must be securely tightened to
prevent spillage
Winter operation
During the winter months, battery capacity
tends to decrease as temperatures drop.
Additionally, more power is consumed while starting, and the headlights, heater, rear window defogger, etc., are used more
frequently. Curtail unnecessary power
consumption, particularly in city traffic or when travelling short distances only. Let your
Porsche dealer test the battery's capacity
before winter sets in. A well charged battery
will not only prevent starting problems but will
also live longer.
Battery charging
Automotive batteries lose their efficiency when not in use. The charge available in your
battery can be measured with a hydrometer.
We recommend that battery voltage be tested
by your Porsche dealer who has the
appropriate equipment. If the car is not driven
for prolonged periods, the battery


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must be charged at least every 6 weeks. A
discharged battery allows rapid formation of
sulfates, leading to premature deterioration of
the plates.
WARNING
Charge battery in a well ventilated area.
Keep away from open flame or electrical
spark. Do not smoke. Hydrogen gas
generated by the battery is explosive.
Electrolyte fluid that may spill during charging should be washed off with a solution of warm water and baking soda to neutralize the acid. If you get electrolyte in your eyes or on your
skin, immediately rinse with cold water for
several minutes and call a doctor.
Never charge a frozen battery. It may
explode because of gas trapped in the ice.
Allow a frozen battery to thaw out first. Never use a fast charger as a booster to start the engine. This may seriously damage the
vehicle's electrical system and the charger.
Fast charging a battery is dangerous and
should only be attempted by a competent
mechanic with the proper equipment.
Slow battery charging
WARNING
Heed all warnings and follow instructions
that come with your battery charger.


Disconnect battery cables and remove the
battery.
All vent caps should be open. If fluid level is low, it should be topped up to the full mark in
each cell.
Connect charger cables.
Charger cables must be connected
POSITIVE (+) to POSITIVE (+) and
NEGATIVE (-) to NEGATIVE (-).
Do not connect or disconnect charger cables while charger is operating. Switch on charger. Normally, a battery should be charged at no
more than 10 percent of its rated capacity.
Rated capacity of the battery in your vehicle
is listed on the battery housing.
After charging, turn off charger and disconnect charger cables. Tighten the vent caps and reinstall battery.



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Emergency Starting with Jumper Cables
WARNING
Improper use of booster battery to start a
vehicle may cause an explosion.
Lead-acid batteries generate explosive
gases. Keep sparks, flame and lighted
cigarettes away from batteries.
Do not charge a frozen battery, thaw it out
first. Gas trapped in the ice may cause an
explosion.
No attempt should be made to jump start any vehicle with a low electrolyte level in the
battery.
Check electrolyte level of each cell. If
necessary, fill with distilled water to just
above plates.
Make sure the voltage of both batteries is the same. The capacity (Ah) of the booster battery
should not be lower than that of the
discharged battery.
Vehicle with discharged battery: turn off
lights and accessories, remove key, move
lever to N or P and set parking brake.
Vehicle with booster battery should not be
running. Disconnect ground cable.
Remove vent caps from booster battery and
discharged battery. Preferably lay a cloth
over open vents to reduce explosion hazard.

How to use jumper cables WARNING
To avoid serious personal injury and damage to the vehicle, heed all warnings
and instructions of the jumper cable
manufacturer. The jumper cables must be long enough so that neither vehicles nor cables touch
another.
Improper hook-up of jumper cables can
ruin the alternator.
Always connect POSITIVE (+) to POSITIVE
(+), and NEGATIVE (-) to ground on engine
block.
1. Connect clamp of plus-cable to positive (+) terminal of discharged battery (1).
2.
Connect clamp on opposite end of cable to
positive (+) terminal of booster battery (2).
3.
Connect clamp of minus-cable to negative
(-) terminal of booster battery (3).
4.
Connect clamp on opposite end of cable to
a bare metal part bolted directly to the
engine block or to the engine block itself (x)
of car with discharged battery. Connect
clamp as far away from battery as possible.
5. Start engine in the usual manner. If engine
fails to start, do not continue to crank but
contact nearest workshop.
6.
With engine running, remove jumper cables from both cars in exact reverse order: Steps 4 through 1.


7. Reconnect ground cable of booster battery.
A - Discharged Battery
B - Booster Battery
Do not try to start car by pushing or towing.
Damage to the catalytic converter, the
transmission, and/or other components of the
car may result.

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