Instrument cluster and dashboard lights are not lighted.

geneo12

New member
Sep 5, 2024
7
0
1
The background narrative. I purchased a 1994 E320 wagon that had been stored in a garage for about the last ten years. The automobile is operational and, other from requiring several rubber and standard wear components to be replaced, is in generally satisfactory shape. Throughout the last month, I have dedicated every weekend and countless late nights to making the vehicle operational. It is quite probable that several further postings may follow; nonetheless, I am endeavoring to keep each topic distinct for everyone's convenience.
Upon purchasing this, the lamp-out warning light was the only indicator lighted while the engine was operational. All additional warning indicators would activate when the key is turned to position two. All gauges function well. There is an absence of backlighting throughout the car throughout. The right rear parking light is inoperative, and one inside bulb at the left rear door pillar is also inoperative. The factory radio is inoperative, with the exception of the flashing red security light.
I changed the headlight switch, resolving the issue with the absence of low beams. I inspected all the fuses in the engine compartment, cleaned and replaced any questionable components, and then verified for power on both terminals. I removed the wiper/signal relay and conducted a thorough cleaning and inspection of all components. This action made the blinkers functional. I removed and sanitized the headlight relay. I replaced the malfunctioning danger switch. The danger lights are operational, and the switch glows when activated. I removed the instrument cluster and conducted a visual inspection and testing of each bulb and socket using an ohmmeter. All have been tested successfully and are the appropriate OEM bulbs. I conducted a visual inspection and testing of the "red fuse," and it is functioning properly. I adjusted the dimmer and discovered that the solder connection was severed, so I resoldered and cleaned it, then verified its functionality with an ohmmeter. It was verified as functioning OK, so I proceeded with the reinstallation. I subsequently restored the cluster, although the backlights remain nonfunctional. I reexamined the cluster and used a test light to inspect each wire connected to it. The only wire carrying electricity is the 12v spade connection linked to the back of the tachometer/clock. I see no indications of degradation in any of the wires encountered inside the interior, and the wiring harness beneath the engine hood is a Denso replacement.
I am attempting to ascertain if any additional wire, other from the tachometer/clock wire, is required to provide electricity for the backlights in the cluster.
 
I apologize for my lack of knowledge; this is the first Mercedes I have examined beneath the hood since the mid-1990s. I could not recall any details about the eco wiring until many days after I hauled it home and read about the environmental issues here. My father was a Mercedes technician, and a long-forgotten recollection resurfaced of me standing by a vehicle such to this one as he replaced the harness. I promptly exited and examined the wiring beneath the battery, discovering the Delphi label. I examined the wiring connected to the sensors on the thermostat casing, which seemed to be clean and modernized. Upon removing the fuse box top and relays, I saw that the wiring below seemed to be in excellent shape considering its age. I see little yellowing and no evidence of cracking, crumbling, or any apparent indicators of degradation. All wiring I have seen in the dashboard, behind the front carpets, and behind the cargo sections seem and feel similarly functional. I am uncertain about where further to search for "all remedied."
 
Is there any information on if the wiring schematic was modified after the lift installation?
 
altered subsequent to lifting?
It is crucial to be aware of the ecojunk modifications initiated with the 1993 3.2/2.8 models with the HFM-SFI M104, namely concerning the main harness, throttle body actuator, and lower starting harness. All three components need inspection, since the majority of previous owners simply attended to the main harness. The lower harness is a do-it-yourself project; retain all connections for repurposing, since most are no longer available, and improvise as necessary. Tuberculosis treatment is not inexpensive; I am aware of just two respectable individuals or establishments that may be trusted. Additional elements may exist.

about the TB decal

You may need to meticulously cut open the outer sheath to physically check the label if the date is unreadable.
 
Thank you; that should address a knowledge deficiency. By post lift, I refer to post-facelift. The W124 had a facelift in 1993. I inquire because I have acquired five manuals, and only one, the MB maintenance handbook, explicitly indicates its applicability to my E320 wagon 124.092/104.992. While I appreciate having it, it is of little use at this time. The Haynes handbook explicitly indicates on the rear cover that it does not include the E-Class range debuted in August 1993, which was quite disappointing. I assumed many aspects would be analogous, so I purchased it nonetheless; nevertheless, I am uncertain whether the wiring diagrams are accurate. I discovered MB chassis and body service manuals on eBay and reached out to the vendor to verify their compatibility with my car, receiving confirmation that they were indeed appropriate. I completed the order, and three weeks later, upon arrival, I opened the books to find that my car is not included, despite being produced in 1992. I have had them for two days and am uncertain about the reliability of the wiring information. Given their expense, I prefer to return them promptly if they are incorrect and seek the appropriate replacements.