1997 E420 Analog Gauge Malfunction
Thread Starter
Newbie
Joined: May 2003
Posts: 8
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From: Los Gatos, CA
1997 E420
1997 E420 Analog Gauge Malfunction
I'm observing some erratic behavior with the analog gauges on my 1997 E420 with 60K miles on it. Following are the symptoms -
1. Sometimes when the engine is started, all analog gauges (fuel, speed, temp, RPM) stay in the OFF position except the speedometer needle which jitters around the 0 mph mark. No change in gauge behavior while driving.
2. Other times when the engine is started, all the analog gauges work fine including the speedometer. This continues until the engine is shut off. At this point the speedometer needle jitters for about 5 seconds around the 0 mph mark and then stops. A click (relay?) is heard from behind the radio area at the same time the jittering stops. Appears to be an electrical switch.
3. Generally these analog gauges work OK when the engine is started in the morning or from a cold start. Conversely, the gauges do not work when the engine is started after the car is already warmed up.
4. The digital gauges (Odometer, outside temp, clock) always work OK.
Any thoughts on this ??
1. Sometimes when the engine is started, all analog gauges (fuel, speed, temp, RPM) stay in the OFF position except the speedometer needle which jitters around the 0 mph mark. No change in gauge behavior while driving.
2. Other times when the engine is started, all the analog gauges work fine including the speedometer. This continues until the engine is shut off. At this point the speedometer needle jitters for about 5 seconds around the 0 mph mark and then stops. A click (relay?) is heard from behind the radio area at the same time the jittering stops. Appears to be an electrical switch.
3. Generally these analog gauges work OK when the engine is started in the morning or from a cold start. Conversely, the gauges do not work when the engine is started after the car is already warmed up.
4. The digital gauges (Odometer, outside temp, clock) always work OK.
Any thoughts on this ??
Thread Starter
Newbie
Joined: May 2003
Posts: 8
Likes: 0
From: Los Gatos, CA
1997 E420
There was no easy solution. I had to have the whole instrument cluster replaced by the dealer in San Jose. However, because this was the second time the cluster was being replaced (the first time was under warranty) the dealer agreed to absorb half the $1600 replacement cost after I complained to them, in writing, that I expected MBZ to stand behind the quality and reliability of their cars.
MBWorld Fanatic!
Joined: Mar 2002
Posts: 1,537
Likes: 2
From: Arizona, USA
W205 C300
With gauge readings on the instrument cluster, there is an easy way to check if there is an issue with the cluster itself or with the inputs going to the cluster. Put your Climate Control in Diagnostic mode by pressing and holding the REST button. (Do a search on Diagnostic AC mode) to get the full details. You can compair the raw data readings for RPMs and Speed between the cluster and the readings on the AC control screen. If the car is moving and both show a zero reading, or if you are at idol and the RPMs show zero on both, then you may have a bigger issue. If the reading are correct on the climate control display but are not on the instrument cluster, then the cluster is at fault. You can find used ones on ebay or I have one from a 99 E55 that I can sell to you. I pulled the AMG faces off of it but the electronics worked fine.
