Dash lights out, a dead gauge or a stopped clock all lead to the same job: removing the instrument cluster. On an R107 it is not difficult if you take your time and protect the dash.
Before you start
- Disconnect the battery.
- Check the dash light dimmer. If it is turned fully down, the dash lights will not work.
- Check the fuses. See electrical troubleshooting.
How to remove the cluster
The R107 cluster is held in the dash by a friction fit and is pushed out from behind or pulled out from the front, depending on year. A common method:
- Remove the lower dash cover (the knee pad) on the driver’s side to reach behind the cluster.
- Push the cluster gently forward from behind while pulling from the front. Some owners use cluster removal hooks at the edges.
- Tilt the cluster out far enough to reach the connectors.
- Disconnect the speedometer cable (on cars with a mechanical speedometer), the oil pressure line or sender wire, and the electrical connectors. Label each one.
Protect the dash top and the steering column with a towel. The cluster glass and needles are fragile. Follow the factory manual for your year.
Bulb types
The cluster uses small wedge-base and capped bulbs in plastic holders that twist out from the back. Common types are 1.2W and 3W bulbs, with different holders depending on the position. Check the size printed on the old bulb and replace them all while the cluster is out. LED replacements are available, but some can confuse the warning lights or the dimmer; choose ones made for older cars.
Dimmer
The rheostat dims the cluster and switch lighting. If the lights flicker when you turn it, the rheostat contacts are worn. Cleaning sometimes helps; otherwise replace it.
Gauges not working
- Fuel gauge: usually the tank sender. See fuel gauge not working.
- Temperature gauge: check the sender on the engine and the wiring before the gauge.
- Oil pressure gauge: most R107s use a mechanical gauge fed by a small oil line. A leaking line needs immediate attention. See oil pressure.
- Speedometer: a broken cable or a worn speedometer drive. Also see odometer repair.
- Several gauges at once: check the cluster ground and the fuse.
Cluster repair services
Instrument specialists can repair gauges, odometer gears, clocks and circuit boards, and can restore faded faces. Send the whole cluster if you are not sure which part has failed.
Quick answers
- Can I change bulbs without removing the cluster? Some can be reached from behind with the knee pad removed, but it is much easier with the cluster out.
- Will LEDs work? Some do; choose ones designed for older cars.
- Why does my oil pressure gauge leak? The oil line or its fittings at the back of the cluster. Fix it immediately.
- Is the clock in the cluster? On most cars, yes. See clock not working.
