When a Honda arrives to the shop with a host of transmission solenoid electrical faults such as P0753, P0758, P0763, P1768 and/or P1773 along with P1298; Electronic Load Detector (ELD) Voltage High, do not ignore the ELD code. In fact make it the first code to diagnose and correct. In near all cases, the cause of all the solenoid electrical codes is due to the failed ELD circuit.
The ELD is located in the under hood fuse box. When it fails it causes the alternator to overcharge which causes high system voltage which results in causing solenoid codes to be stored falsely.
NOTE: The above complaints can also be caused by the failure of the No. 15 fuse on earlier models or the No. 4 fuse on later models, both of which are in the underdash fuse box.
The No. 15 fuse usually blows on Civics due a wire harness under the intake manifold rubbing through the insulation causing a short to ground. When this fuse blows, the transmission will be stuck in 4th gear, the ELD will not have power and the speedometer will be inoperative.
The ELD could easily be mis-diagnosed if the way it operates is unknown. The ELD limits the amount of alternator output voltage when there is no electrical load sensed. This puts a lesser load on the engine at idle for emission purposes and provides better fuel economy on the highway. Under this “no load” condition a voltmeter across the battery may show open post voltage only (12.6V). Turn the headlights on, and now, the voltmeter should indicate about 14.6V.
The ELD can be bought separately on some models, while on others the entire underhood fuse box must be bought, check with your local Honda dealer.
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