Tohatsu 50 TLDI 3 Fault Lights - Ideas?

[whoopy]

I have a 2001 50hp Tohatsu TLDI. After starting the engine the 3 fault lights (L-oil level, Mid Temp, R-Battery Connection) flash on and off. <br /><br />I have had this problem twice. The first time I misread the owners manual and replaced the 4 year old battery with a Gp24 DieHard deep cycle 3 weeks ago and the engine ran fine during two subsequent outings. After a cold (90 deg ambient) start today the the problem repeated. The three warning lights began flashing and the engine speed was reduced to idle by the engine control. The engine ran rough.<br /><br />For trouble shooting I checked the battery - ok, tried a second battery - same problem. The voltage at the battery with engine at idle was 14.4 vdc which I thought was high but I'm not an experienced mechanic. When I touched the positive battery cable to the terminal I'm sure I detected a small "snap" but could measure no current with the key off (no other circuits were connected). Also noticed that the spark plug wires do not snap onto the spark plug in a positive way like all other engines I have worked on. <br /><br />The manual says "Consult your dealer . . . " <br /><br />Questions:<br />1. Is there anything I can check before hauling? <br />2. Can anyone recommend a good service manual for this engine? <br /><br />thanks

 

[TOHATSU GURU]

Re: Tohatsu 50 TLDI 3 Fault Lights - Ideas?

It's unlikely that your battery is a 100 to 120 amp type. Anything less than 100 will "fault" the engine. Most marine batteries are 70 amp...and not designed for DFI engines. Also, keep in mind that 100 amps is the minimum and when you go the minimum it will not take much going wrong to drop you in the "not enough" zone again. <br /><br />The spark plug boot should be a positive snap...sounds like something is wrong there. For a service manual you can visit:<br /><br />www.tohatsu.com/tech_info/index.html

 

[ziemann]

Re: Tohatsu 50 TLDI 3 Fault Lights - Ideas?

Elvin- please correct me if I am wrong here. <br /><br />If it is low voltage (dropping below 10 volts), just the battery light should flash. If it is high voltage, he would get all 3 flashing.<br /><br />Potential causes would be:<br /><br />1. High battery voltage (doubtful- approx 18 volts or more)<br />2. Fault in the throttle position sensor or its wiring harness (possible- would cause an irradic idle or RPM variation)You may have to reset the TPS & ECU values if there is a fault in TPS 1 or 2.<br />3. Low Fuel rail pressure (not possible, because your engine runs. Low fuel rail pressure would not allow it to run)<br /><br />I would agree with Elvin- most folks "cheap out" on batteries and do not buy the minimum 100-120 amp that is required for this system. But this MAY NOT be your problem.

 

[whoopy]

Re: Tohatsu 50 TLDI 3 Fault Lights - Ideas?

Thanks for the your inputs. For the lack of nothing better to do I removed the battery cables (which were properly tightened when the problem occured) and wire brushed the battery terminals until they were nice and shiny. After reinstallation the engine operated normally.<br /><br />The Die Hard I installed had specs (75 AH/500 CCA) well below the FAQ specs. Incidently my owner's manual has no stated battery requirements on the Specifications page or elsewhere. <br /><br />Anyway it is foolhardy to argue with the mfg requirements but . . . a couple of months ago I inquired from Tohatsu what the starter draws as I wanted to change battery location. The rep said the starter only draws 24 amps max. How do we go from 24 amps to 100s for a electronic fuel injection controller when the alternator can only restore 280 watts? Go figure. Makes me want to carry two or three spare batteries.<br /><br />I would really appreciate any information on other failures or conditions that can trigger a fault causing all three lights to blink. High voltage wasn't the problem at least with the engine working properly.

 

[TOHATSU GURU]

Re: Tohatsu 50 TLDI 3 Fault Lights - Ideas?

There are pages of fault codes in the service manual.

 

[jshoes52]

Re: Tohatsu 50 TLDI 3 Fault Lights - Ideas?

Whoopy, did you ever get this problem figured out? I've had the same 3 warnings lites flashing and forced idle speed at sporadic times the last three times I used the boat (90hp tldi). My starting battery is 800cca and 1000 mca which Elvin says is too small, but I've never gotten a low voltage warning lite. I'm going to see the dealer and replace my house battery with whatever he uses for tldi's if he recommends it.