FAQ for 7xx/9xx/90 Cars
Failures. I do not believe it is possible to buy the gear, but it is
definitely possible to have it fixed. VDO in Winchester, VA, and other
places advertise. Get a copy of Hemmings motor news, you will find them
in there. I believe the gears break due to people resetting the odometers
while the car is moving. I have never seen this written as a warning in
the owners manuals, but that is the best explanation I have seen. [Note
on rebuilder:] Palo Alto (CA) Speedometer Service: (415) 323-0243. I have
yet to use their services, but they were recommended by a local shop here
in Boise as the best in the business. I called them last summer, contemplating
sending my wife's speedo in for repair, but I haven't gotten around to
it yet. The price they quoted was around $90, just to fix the odometer.
[Another:] just had my electric speedo/odo repaired. know this is a common
problem so thought I'd pass along the shop's name and number.
A+ emissions and speedometer repairs (Chris
(904) 642-8120); 3122 #9 Leon Road ;Jacksonville, FL 32246
He's a straight shooter and keeps a clean
shop. Does lots of Volvo speedo work through the mail.
[Another referral:] I wanted to pass
on contact information for a company I found here in Austin that works
on Volvo (and other makes) speedometers. Its called Overseas Speedometer
and you can get their contact information at www.speedometer.com . I just
dropped off my speedometer to get re-calibrated for my V8 conversion and
to get the odometer working again. A couple of Volvo shops around here
gave him a good reference so I thought I'd pass it on.
Fluctuates. [Query:] My wife’s 1991 740 sedan speedometer needle
simply drops to zero (as if someone pulled a socket from the wall) At this
moment the odometer and trip odo also quit. Very occasionally, when driving,
at highway speeds, the speedometer needle will jump back up to the correct
speed, and the odometer starts working, but usually after a 1/2 mile or
about 40 seconds, the needle falls back to zero and the odometer quits.
Other times everything works fine for hundreds of miles. Often when starting
the car after is has been parked, odometer and speedometer never work at
all. [Response 1: Don Foster] Check the connection at
the speedo sensor. It's in the differential cover, about 3" above the filler
plug. Be sure it's mechanically secure, and check the contacts (both sensor
and connector) for signs of corrosion or oxidation. As much as possible,
examine the harness for any signs of a break or tear, or for signs the
wire might have been cut. If it's not wiring, then it's either
the sensor or the speedometer head (which is electronic). Possibly,
the power supplied to the speedo head where it's mounted in the dash cluster
is intermittent. [Response 2: Scott] Check the instrument cluster
grounds under the dash and in the right footwell. In 88 there
were some 700 series cars that would register up to 60 mph while sitting
still and the grounding problem was the cause.
Relay and ABS Lamp. [Query:] I recently brought my 1987 Volvo
760 GLE with 200,000 miles in for repair after I noticed that the speedometer,
odometer and cruise control stopped functioning. The car does
have ABS and the ABS dashboard light also went on full-time just about
the same time as the speedo/odometer/cc went out. [Response:
Zippy] The speedometer converter is a relay looking device that is under
the left side modesty panel (under dash piece) that has its own fuse mounted
to the top of it. You hadn't recently jump started your car's battery
have you? Done incorrectly it is very common for this hidden fuse to blow,
rendering ABS and the speedometer inoperative. This only happens on the
older ABS cars. See also ABS
Lamp Lights After Start-up
Instrument Cluster Removal. It's very simple. take a super slim screwdriver
and remove the small plastic cap surrounding the small clock set knob on
the left and the cap surrounding the dash light dimmer on the right. Under
each of these is a phillips screw. Remove and pull the whole cluster out.
Don't even need to remove the steering wheel. If it 's the first time out,
the wiring will be held in tight behind the dash by plastic ties. You can
cut these ties which will afford you enough room to twist the cluster around
and replace any bulbs etc, or mark each electrical plug and unplug enough
of them to give you the room you need.
Instrument Cluster Removal. [Query:] I can not figure out how to get
the instrument cluster out of my 89 760. It looks like all of the trim
around the dash switches has to come off, then take a couple of screws
out on top of the dash insert. I can't seem to make anything move.
[Response: Chris Ascoli] I found out the hard way. Besides the two
screws in the upper black insert, there are I believe 3-4 more screws hiding
behind the air vents, one per vent. Take each air vent and push the
top all the way into the dash as if you want to shoot the air up at the
ceiling of the car. Once you do this, you should be able to see the screw
in the upper portion of the plastic JUST behind the top of the vent.
It's kind of tricky to get at, but you should be able to squeeze a Phillips
head in there and remove them. Forget to do this and you'll hear a Crrrrrraaaack
of the plastic housing surrounding the temp controls, etc. As you can imagine,
that's how I found the screws. Chilton's did a fantastic job of NOT
telling me about them. Thank God I didn't break it enough so that it hung
away from the dash when reinstalled.
Once you get the vent
screws, just pry with a little force and it should come out. But if it
seems to hold up somewhere, check for any other screws at the binding point.
The vent ones are definitely key though.
Instrument Cluster Removal. [Query:] How do I remove the
instrument cluster in my 940? [Responses: Abe Crombie and IanB]
We got it out with a small screwdriver which will go through the slots
in the side of the plastic bezel. You will feel a spring clip as
you push into slot. Push the clip hard while pulling toward you with the
shank of driver; the clips are attached to the dash and are also robust,
not easy to damage. The surround is alloy and is held by the cluster
screws. There are lugs cast into the sides of the surround
onto which the clips lock. Do one side only, it should come out easily
once you get one to let go. One clip each side, nothing else holds
it in. After you get it out remove the cluster by taking out (4)
Torx screws and it's out. If it's turbo you have a gauge hose
to disconnect at a joint about 8 or 10 inches from gauge. The latter is
easier to do with the kickpanel above brake removed. To replace the
bezel simply push it in and the clips lock onto the lugs.
Instrument Cluster Lamps. [Query:] I have a 740 gtl 87. How I
can replace bulbs behind the clocks (speedometer etc.) [Response:
Peter James ] At the base of the instrument panel under the clock adjustment
and trip reset buttons, towards the ends there are 2 rectangular panels
about 5mm high by 35 mm long. Lever these out with your fingernail. Underneath
there is a phillips head screw. Undo both and the whole instrument assembly
will pull straight out, limited by the wiring harness plugs and the hose
for the boost gauge. I usually disconnect the hose which gives you enough
space to get your hands/fingers in to turn the lamp holders and remove/replace
the globes. You can disconnect the wiring plugs but I don't bother, I put
a mirror up on the top of the dash against the windscreen with bluetack
and work from the drivers seat. Hope this helps.
Switch Panel Lamps. You're actually referring to the switch panels
(or whatever it's called). I don't know offhand if the '89 740 has
the same style of instrument cluster as the earlier ones -- I know the
760's changed in '88, but the 740s didn't until later -- 1990? Anyway,
probably the easiest way to get to a burned out bulb there would be to
remove the instrument cluster. If your instrument cluster has a clock adjustment
knob on the bottom left corner and a dimmer adjustment on the bottom right
corner, the two plastic strips they poke through can be pried off, revealing
two phillips screws. These screws are the only things holding the instrument
cluster in place. Remove them, slide out the cluster, and you should be
able to place it on the dash. Then you can reach down in the opening and
fish around for the burned out bulb. A dentist's mirror or equivalent may
help you in your search. If your '89 has the later style instrument cluster,
it comes out in a similar fashion, but there are clips that hold it in
place located on the sides of the cluster. I've never pulled one of these
out, so I don't know how much more difficult or easy it is compared to
the earlier style.
Indicator Bulb Replacement. Shift Indicator Lamp. [Query:] How
does one replace the bulb that illuminates the gear selector letters?
[Response:] Here’s how it can be replaced:
2.remove plastic cover under hand brake
3.remove two screws that 2. revealed
4.remove plastic cover that covers shift gate
5.Look under shift gate on left side for two wires connected to light
6.pull down gently on wires and the light appears
7.replace bulb and reinstall in reverse order
Lights Flickering: Bad Alternator Brushes. [Query:] We just replaced
our battery because as we drove the warning lights were constantly flickering
on and off (plus sometimes we had to jumpstart the car to start it). Now
the car starts fine but the warning lights continue to flicker. Any idea
on what could be the problem? [Response: Russell Smith] Check the
brushes in the voltage regulator. Most likely they are worn out, causing
the idiot lights to flicker and preventing the battery from charging adequately.
Stop Working Intermittently. Has anyone experienced a situation where
all the gauges in the binnacle act as if they are not getting any power?
2. Has anyone experience a situation similar to 1. above, but where the
gauges seem to take turns taking a swan dive? [Response:] Have seen this
problem on a 85 / 740 turbo. I took out the instrument cluster and tightened
every screw and connector I could get at and this fixed the problem. Talking
to a Volvo mechanic, he said there is also likely that a ground is bad
on the computer module situated near the passenger side, side wall.
[Response 2:] For what it's worth, my '90 745 had the gauge problem intermittently.
Drove me crazy, and the dealer "tightened the grounds" four times, each
with a positive effect for a short while. They did give up, saying it was
mostly likely a cracked p.c. board in the dash, which would fail as it
flexed. Wouldn't know without pulling the dash. I sold it. Problem solved.
Gauge Fluctuates. [Query:] I just noticed my heat gauge flutters
from the left to middle (not into the hot Zone) . There does not seem to
be any pattern to this, smooth roads or bumpy, acceleration or slowing
, whatever. It looks normal for a while, and then starts getting the jitters.
[Response: Steve Ringlee] To test your gauge, get an appropriate resistor
from an electronics store (preferably with a 5W or above rating +/-5% tolerance),
solder an alligator clip to one end and a quick disconnect connector to
the other. Pull your gauge
temperature sensor connector from the sensor (the one under number
two cylinder intake manifold on B230F engines) and insert the quick disconnect
into the half of the connector wired to the gauge (not ground). I recall
that out of the panel this wire is yellow-white. Check your wiring diagram
to confirm this. Attach the alligator clip to ground and turn on the ignition.
Your gauge should read in the hot end if it works. If it doesn't, then
either the gauge or the wiring harness to the gauge is faulty. Clean wiring
connectors with electronics connection cleaner (such as DeOxIt) and test
again. If it reads correctly, then the sensor is bad.
Resistor ratings for 7XX/94X cars are:
Cars from 82-86: 87 ohms to get a
90C reading at the gauge
Cars from 87-93: 206 ohms to get
a 90C reading at the gauge
Cars from 94 on: 75 ohms to get
a 90C reading at the gauge
Clock Repair. The Clock Works; (Automotive Clock Repair & Quartz
Conversions - Most Service Completed Within 24 hours) at 1745 Meta Lake
Rd., Eagle River, WI 54521-8531Contact: Jerry Magayne Voice or Fax: (715)
479-5759 E-mail: firstname.lastname@example.org
Odometer. I have found a solution: at the pick and pull I can get an
instrument cluster for very cheap (10-25% of the repair estimates). I just
unscrew 8 screws at the back of the board and remove the cowl and lens.
Then take 4 screws out of the white speedo housing to pull it free. This
can be transplanted easily into your recipient cluster and even a slightly
different 1990 model works well in the 86 cluster after removing the service
reminder reset cable that the later ones come with. Who needs that function
anyway? To reset the mileage to your correct (but by now estimated) figure
is also trivial once you remove the small white electric motor that drives
the odometer, and slide the pin holding the small exposed gears. The odometer
digits now rotate freely. No cheating at this point. (The members of this
list are probably the only group of owners who would not be tempted to
roll back mileage, but instead might be tempted to add high status mileage
to their cars!). Most of the speed-odometers are the r9800 variant but
compatibility is something to check for in the replacement. Apparently,
this number keys it to the rear end properly. This is also a swell time
to throw in a large tach if you can get one.
Light Reset in Pre-1990 740. [Procedure:] There is a reset button
on the back side of the instrument cluster. It is located about where the
70 mph reading is, on the back side. You may be able to get your hand up
from the bottom to press the reset by first removing the lower kneepad.
You can also remove the two outer lower screws on the instrument cluster
and gently pull out the instrument panel enough to get your hand behind
to press the reset button. There is just enough slack in the harness to
allow pulling the assembly over the steering column to get at the reset
button. Remove each small plastic cover to expose the mounting screws.
The speed nuts that these two screws go into like to fall off, down into
the dash area. A lot of people just remove the service bulb on this model
to avoid the trouble of having to reset light every 5000 miles.
Light Reset on Post-'89. On the post-’89 700/900's there is a small
black, circular rubber plug in the clear plastic of the instrument cluster.
Carefully remove the plug ... then take a very small phillips screw driver
or even a nail and push in the re-set pin just behind the hole in the clear
plastic. Replace the plug and the service light is re-set.
Control Won't Work or Incorrectly Disengages/Re-engages. [Response
1:] Most common problem that I have seen is either split or disconnected
vacuum hose, or mis-adjusted brake switch (at the pedal) or clutch switch
(if manual tranny). Sometimes it is simply that the brake or clutch pedal
is not fully returning - try lifting up on the pedal with your foot while
driving and see if you can engage the cruise. In addition to the vacuum
switch, check for operation of the brake light switch. I seem to remember
that the vacuum switch will disengage the cruise simply by releasing the
vacuum from the unit, but the brake light switch must activate in order
to release the control unit signal. If you are just tapping the brake lightly
to disengage the cruise (as I often do), but not activating the brake light
switch, then it may simply re-engage as soon as vacuum is applied again.
[Response 2:] Pull hose loose at "T" fitting
aft of throttle servo. Apply vacuum (suck on it, but make sure no
one's watching) to fitting with hoses that run down to pump and into car
to brake pedal defeat switch. If leaks are detected here then find
split hose or go inside and find pedal switch fault. If no leaks detected
then closely inspect the servo for splits or tears. The likelihood
of electrical trouble is far lower than having a hose split or a leaking
[Query:] The cruise control on my sister's
1993-944 will engage only about 10% of the time it is activated. Per past
posts I checked all the vacuum lines and the servo with a Mityvac tester
and they hold a vacuum, indicating no leaks. I also checked the functions
of the cruise switch on the turn signal lever, by disconnecting the harness
connector, with an ohm meter and it checks out. The fuse is also ok. I
tried to use the "B" diagnostic socket with the wire put in the #2
hole. I turned on the ignition and pressed the button and nothing happened,
no codes flashed, not even a 1-1-1.
[Response 3:] There is a separate switch
with a vacuum line attached for the cruise. If the car is manual tranny,
the car would have two switches, one for each pedal. If the switch adjustment
is marginal, i.e., there is not a definite “off”, then the switch needs
to be adjusted. It is adjusted the same way as the brake switch.
[Response 4:] Mine did the same thing
and the problem was the bulb failure relay/device in the relay compartment.
When this fails there is no ground for the cruise and the brake lights
Failure Sensor Lamp Won’t Go Out. [Query:] My left low beam failed,
and my bulb failure warning light dutifully advised me of the need to replace
the bulb. I replaced the left low beam, and all the lights on the car work
now. But, my warning light is still on, though it goes out when I flip
to high beams. Anyone know a fix for this? [Response:] The bulb failure
sensor works on current flow. If the bulbs are miss matched, say a Wagner
bulb on the left and a Sylvania on the right, chances are they have different
resistances. This causes different current flows to each bulb and
the light on the dash will come on. You may just want to change the
other headlight and hope that stops it, or live with it. Also, corrosion
in the connectors in the circuit that the head lights are on can cause
the indicator light to come on. It can be very frustrating, and I
know many people that have pulled the little bulb out of the dash.
Console Lamp Replacement.
[Query:] Does anyone know how to replace the light that illuminates the
inside of the center console and the rear ashtray? I can't figure out how
to get in there. [Response: John R] The plastic panel on the
rear of the centre console clips out, but it is very hard to pull out,
feels like it will break. Try removing ashtray and then gently pulling
around bottom of the panel. Once this panel is removed you can gain access
to lights (also gives you access to the handbrake adjustment).
a Warning Lamp for Loss of Engine Coolant. See Loss
of Coolant Sensor for Volvo 740/940 Cars for more information
as to how to add this sensor and warning lamp.
FAQ for 7xx/9xx/90 Cars
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