This is my mothers car: a 1991 240 DL with 130k or so on the odometer. She called me to complain about the brakes (needs rotor resurfacing), and when I went to test-drive it, after starting the car, none of the auxillary electrical features would work. No radio, no power windows, and no air conditioning/heater blower. I grab the manual and go inside to investigate. When I returned, I started the car again, and everything worked! I get a call yesterday, saying that the car will not start (it cranks but will not fire). All fuses are intact. Could the summer heat be frying my relays? Where should I start? Thanks in advance!

Possibly the ignition switch - try waggling the key when this happens, otherwise possibly corroded fuses - try rotating them in their holders.

Speaking of fuses, check on the 25 Amp blade fuse in holder slightly behind battery, on fender wall. They don't blow often, but contacts get dirty. Failure of that fuse/holder disables spark and fuel flow, thus no-start.

IF you decide to pull the red leads from bottom of fuse holder for any reason, be sure to disconnect the battery ground cable first, as hot leads like to ground on the fender wall or anywhere else they go.
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Formerly Sophie's Maintainer. Sven: '89 245, IPD sways, E-fan conversion, 28+ mpg - auto tranny. 850 mi/week commute.

good advice if you have 83-90. 91up wild goose chase.

good advice if you have 83-90. 91up wild goose chase.

Chase it down to Fuse 6, which takes the place of the 25 amp'r.

Worth a "spin" maybe.
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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.